diff --git a/application/Espo/Controllers/TwoFactorSms.php b/application/Espo/Controllers/TwoFactorSms.php
new file mode 100644
index 0000000000..4de03899c8
--- /dev/null
+++ b/application/Espo/Controllers/TwoFactorSms.php
@@ -0,0 +1,80 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Controllers;
+
+use Espo\Core\Exceptions\Forbidden;
+use Espo\Core\Exceptions\BadRequest;
+
+use Espo\Core\Api\Request;
+
+use Espo\Services\TwoFactorSms as Service;
+
+use Espo\Entities\User;
+
+class TwoFactorSms
+{
+    private $service;
+
+    public function __construct(Service $service, User $user)
+    {
+        $this->service = $service;
+        $this->user = $user;
+
+        if (
+            !$this->user->isAdmin() &&
+            !$this->user->isRegular()
+        ) {
+            throw new Forbidden();
+        }
+    }
+    public function postActionSendCode(Request $request): bool
+    {
+        $data = $request->getParsedBody();
+
+        $id = $data->id ?? null;
+        $phoneNumber = $data->phoneNumber ?? null;
+
+        if (!$id) {
+            throw new BadRequest("No 'id'.");
+        }
+
+        if (!$phoneNumber) {
+            throw new BadRequest("No 'phoneNumber'.");
+        }
+
+        if (!$this->user->isAdmin() && $id !== $this->user->getId()) {
+            throw new Forbidden();
+        }
+
+        $this->service->sendCode($id, $phoneNumber);
+
+        return true;
+    }
+}
diff --git a/application/Espo/Core/Authentication/TwoFactor/Sms/SmsLogin.php b/application/Espo/Core/Authentication/TwoFactor/Sms/SmsLogin.php
new file mode 100644
index 0000000000..8a72317cc0
--- /dev/null
+++ b/application/Espo/Core/Authentication/TwoFactor/Sms/SmsLogin.php
@@ -0,0 +1,104 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Authentication\TwoFactor\Sms;
+
+use Espo\ORM\EntityManager;
+
+use Espo\Entities\User;
+use Espo\Entities\UserData;
+
+use Espo\Repositories\UserData as UserDataRepository;
+
+use Espo\Core\Authentication\TwoFactor\Login;
+use Espo\Core\Authentication\Result;
+use Espo\Core\Authentication\ResultData;
+use Espo\Core\Authentication\FailReason;
+use Espo\Core\Api\Request;
+
+class SmsLogin implements Login
+{
+    private $entityManager;
+
+    private $util;
+
+    public function __construct(EntityManager $entityManager, Util $util)
+    {
+        $this->entityManager = $entityManager;
+        $this->util = $util;
+    }
+
+    public function login(Result $result, Request $request): Result
+    {
+        $code = $request->getHeader('Espo-Authorization-Code');
+
+        if (!$code) {
+            $this->util->sendCode($result->getLoggedUser());
+
+            return Result::secondStepRequired($result->getUser(), $this->getLoginData());
+        }
+
+        $loggedUser = $result->getLoggedUser();
+
+        if ($this->verifyCode($loggedUser, $code)) {
+            return $result;
+        }
+
+        return Result::fail(FailReason::CODE_NOT_VERIFIED);
+    }
+
+    private function getLoginData(): ResultData
+    {
+        return ResultData::createWithMessage('enterCodeSentBySms');
+    }
+
+    private function verifyCode(User $user, string $code): bool
+    {
+        $userData = $this->getUserDataRepository()->getByUserId($user->getId());
+
+        if (!$userData) {
+            return false;
+        }
+
+        if (!$userData->get('auth2FA')) {
+            return false;
+        }
+
+        if ($userData->get('auth2FAMethod') !== 'Sms') {
+            return false;
+        }
+
+        return $this->util->verifyCode($user, $code);
+    }
+
+    private function getUserDataRepository(): UserDataRepository
+    {
+        return $this->entityManager->getRepository(UserData::ENTITY_TYPE);
+    }
+}
diff --git a/application/Espo/Core/Authentication/TwoFactor/Sms/SmsUserSetup.php b/application/Espo/Core/Authentication/TwoFactor/Sms/SmsUserSetup.php
new file mode 100644
index 0000000000..c534019249
--- /dev/null
+++ b/application/Espo/Core/Authentication/TwoFactor/Sms/SmsUserSetup.php
@@ -0,0 +1,71 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Authentication\TwoFactor\Sms;
+
+use Espo\Entities\User;
+
+use Espo\Core\Authentication\TwoFactor\UserSetup;
+use Espo\Core\Exceptions\Error;
+
+use stdClass;
+
+class SmsUserSetup implements UserSetup
+{
+    private $util;
+
+    public function __construct(Util $util)
+    {
+        $this->util = $util;
+    }
+
+    public function getData(User $user): stdClass
+    {
+        return (object) [
+            'phoneNumberList' => $user->getPhoneNumberGroup()->getNumberList(),
+        ];
+    }
+
+    public function verifyData(User $user, stdClass $payloadData): bool
+    {
+        $code = $payloadData->code ?? null;
+
+        if ($code === null) {
+            throw new Error("No code.");
+        }
+
+        $codeModified = str_replace(' ', '', trim($code));
+
+        if (!$codeModified) {
+            return false;
+        }
+
+        return $this->util->verifyCode($user, $codeModified);
+    }
+}
diff --git a/application/Espo/Core/Authentication/TwoFactor/Sms/Util.php b/application/Espo/Core/Authentication/TwoFactor/Sms/Util.php
new file mode 100644
index 0000000000..21a3de3d8f
--- /dev/null
+++ b/application/Espo/Core/Authentication/TwoFactor/Sms/Util.php
@@ -0,0 +1,329 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Authentication\TwoFactor\Sms;
+
+use Espo\Core\Exceptions\Error;
+use Espo\Core\Exceptions\Forbidden;
+
+use Espo\Core\Utils\Config;
+use Espo\Core\Sms\SmsSender;
+use Espo\Core\Sms\SmsFactory;
+use Espo\Core\Utils\Language;
+use Espo\Core\Field\DateTime;
+
+use Espo\ORM\EntityManager;
+use Espo\ORM\Query\Part\Condition as Cond;
+
+use Espo\Entities\User;
+use Espo\Entities\Sms;
+use Espo\Entities\TwoFactorCode;
+use Espo\Entities\UserData;
+
+use Espo\Repositories\UserData as UserDataRepository;
+
+use const STR_PAD_LEFT;
+
+class Util
+{
+    /**
+     * A lifetime of a code.
+     */
+    private const CODE_LIFETIME_PERIOD = '10 minutes';
+
+    /*
+     * A max number of attempts to try a single code.
+     */
+    private const CODE_ATTEMPTS_COUNT = 5;
+
+    /**
+     * A length of a code.
+     */
+    private const CODE_LENGTH = 6;
+
+    /**
+     * A max number of codes tried by a user in a period defined by `CODE_LIMIT_PERIOD`.
+     */
+    private const CODE_LIMIT = 5;
+
+    /**
+     * A period for limiting trying to too many codes.
+     */
+    private const CODE_LIMIT_PERIOD = '20 minutes';
+
+    private $entityManager;
+
+    private $config;
+
+    private $smsSender;
+
+    private $language;
+
+    private $smsFactory;
+
+    public function __construct(
+        EntityManager $entityManager,
+        Config $config,
+        SmsSender $smsSender,
+        Language $language,
+        SmsFactory $smsFactory
+    ) {
+        $this->entityManager = $entityManager;
+        $this->config = $config;
+        $this->smsSender = $smsSender;
+        $this->language = $language;
+        $this->smsFactory = $smsFactory;
+    }
+
+    public function storePhoneNumber(User $user, string $phoneNumber): void
+    {
+        $this->checkPhoneNumberIsUsers($user, $phoneNumber);
+
+        $userData = $this->getUserDataRepository()->getByUserId($user->getId());
+
+        $userData->set('auth2FASmsPhoneNumber', $phoneNumber);
+
+        $this->entityManager->saveEntity($userData);
+    }
+
+    public function verifyCode(User $user, string $code): bool
+    {
+        $codeEntity = $this->findCodeEntity($user);
+
+        if (!$codeEntity) {
+            return false;
+        }
+
+        if ($codeEntity->getAttemptsLeft() <= 1) {
+            $this->decrementAttemptsLeft($codeEntity);
+            $this->inactivateExistingCodeRecords($user);
+
+            return false;
+        }
+
+        if ($codeEntity->getCode() !== $code) {
+            $this->decrementAttemptsLeft($codeEntity);
+
+            return false;
+        }
+
+        if (!$this->isCodeValidByLifetime($codeEntity)) {
+            $this->inactivateExistingCodeRecords($user);
+
+            return false;
+        }
+
+        $this->inactivateExistingCodeRecords($user);
+
+        return true;
+    }
+
+    public function sendCode(User $user, ?string $phoneNumber = null): void
+    {
+        if ($phoneNumber === null) {
+            $phoneNumber = $this->getPhoneNumber($user);
+        }
+
+        $this->checkPhoneNumberIsUsers($user, $phoneNumber);
+        $this->checkCodeLimit($user);
+
+        $code = $this->generateCode();
+
+        $this->inactivateExistingCodeRecords($user);
+        $this->createCodeRecord($user, $code);
+
+        $sms = $this->createSms($user, $code, $phoneNumber);
+
+        $this->smsSender->send($sms);
+    }
+
+    private function isCodeValidByLifetime(TwoFactorCode $codeEntity): bool
+    {
+        $period = $this->config->get('auth2FASmsCodeLifetimePeriod') ?? self::CODE_LIFETIME_PERIOD;
+
+        $validUntil = $codeEntity->getCreatedAt()->modify($period);
+
+        if (DateTime::createNow()->diff($validUntil)->invert) {
+            return false;
+        }
+
+        return true;
+    }
+
+    private function findCodeEntity(User $user): ?TwoFactorCode
+    {
+        return $this->entityManager
+            ->getRDBRepository(TwoFactorCode::ENTITY_TYPE)
+            ->where([
+                'method' => 'Sms',
+                'userId' => $user->getId(),
+                'isActive' => true,
+            ])
+            ->findOne();
+    }
+
+    private function getPhoneNumber(User $user): string
+    {
+        $userData = $this->getUserDataRepository()->getByUserId($user->getId());
+
+        if (!$userData) {
+            throw new Error("UserData not found.");
+        }
+
+        $phoneNumber = $userData->get('auth2FASmsPhoneNumber');
+
+        if ($phoneNumber) {
+            return $phoneNumber;
+        }
+
+        if ($user->getPhoneNumberGroup()->getCount() === 0) {
+            throw new Error("User does not have phone number.");
+        }
+
+        return $user->getPhoneNumberGroup()->getPrimary()->getNumber();
+    }
+
+    private function checkPhoneNumberIsUsers(User $user, string $phoneNumber): void
+    {
+        $userNumberList = array_map(
+            function (string $item) {
+                return strtolower($item);
+            },
+            $user->getPhoneNumberGroup()->getNumberList()
+        );
+
+        if (!in_array(strtolower($phoneNumber), $userNumberList)) {
+            throw new Forbidden("Phone number is not one of user's.");
+        }
+    }
+
+    private function checkCodeLimit(User $user): void
+    {
+        $limit = $this->config->get('auth2FASmsCodeLimit') ?? self::CODE_LIMIT;
+        $period = $this->config->get('auth2FASmsCodeLimitPeriod') ?? self::CODE_LIMIT_PERIOD;
+
+        $from = DateTime::createNow()
+            ->modify('-' . $period)
+            ->getString();
+
+        $count = $this->entityManager
+            ->getRDBRepository(TwoFactorCode::ENTITY_TYPE)
+            ->where(
+                Cond::and(
+                    Cond::equal(Cond::column('method'), 'Sms'),
+                    Cond::equal(Cond::column('userId'), $user->getId()),
+                    Cond::greaterOrEqual(Cond::column('createdAt'), $from),
+                    Cond::lessOrEqual(Cond::column('attemptsLeft'), 0),
+                )
+            )
+            ->count();
+
+        if ($count >= $limit) {
+            throw new Forbidden("Max code count exceeded.");
+        }
+    }
+
+    private function generateCode(): string
+    {
+        $codeLength = $this->config->get('auth2FASmsCodeLength') ?? self::CODE_LENGTH;
+
+        $max = pow(10, $codeLength) - 1;
+
+        return str_pad(
+            (string) random_int(0, $max),
+            $codeLength,
+            '0',
+            STR_PAD_LEFT
+        );
+    }
+
+    private function createSms(User $user, string $code, string $phoneNumber): Sms
+    {
+        $fromNumber = $this->config->get('outboundSmsFromNumber');
+
+        $bodyTpl = $this->language->translate('yourAuthenticationCode', 'messages', 'User');
+
+        $body = str_replace('{code}', $code, $bodyTpl);
+
+        $sms = $this->smsFactory->create();
+
+        $sms->setFromNumber($fromNumber);
+        $sms->setBody($body);
+        $sms->addToNumber($phoneNumber);
+
+        return $sms;
+    }
+
+    private function inactivateExistingCodeRecords(User $user): void
+    {
+        $query = $this->entityManager
+            ->getQueryBuilder()
+            ->update()
+            ->in(TwoFactorCode::ENTITY_TYPE)
+            ->where([
+                'userId' => $user->getId(),
+                'method' => 'Sms',
+            ])
+            ->set([
+                'isActive' => false,
+            ])
+            ->build();
+
+        $this->entityManager
+            ->getQueryExecutor()
+            ->execute($query);
+    }
+
+    private function createCodeRecord(User $user, string $code): void
+    {
+        $this->entityManager->createEntity(TwoFactorCode::ENTITY_TYPE, [
+            'code' => $code,
+            'userId' => $user->getId(),
+            'method' => 'Sms',
+            'attemptsLeft' => $this->getCodeAttemptsCount(),
+        ]);
+    }
+
+    private function getUserDataRepository(): UserDataRepository
+    {
+        return $this->entityManager->getRepository(UserData::ENTITY_TYPE);
+    }
+
+    private function decrementAttemptsLeft(TwoFactorCode $codeEntity): void
+    {
+        $codeEntity->decrementAttemptsLeft();
+
+        $this->entityManager->saveEntity($codeEntity);
+    }
+
+    private function getCodeAttemptsCount(): int
+    {
+        return $this->config->get('auth2FASmsCodeAttemptsCount') ?? self::CODE_ATTEMPTS_COUNT;
+    }
+}
diff --git a/application/Espo/Core/Binding/DefaultBinding.php b/application/Espo/Core/Binding/DefaultBinding.php
index 76b3f46890..c3d4f299f4 100644
--- a/application/Espo/Core/Binding/DefaultBinding.php
+++ b/application/Espo/Core/Binding/DefaultBinding.php
@@ -217,5 +217,10 @@ class DefaultBinding implements BindingProcessor
             'Espo\\Core\\WebSocket\\Sender',
             'Espo\\Core\\WebSocket\\SenderFactory'
         );
+
+        $binder->bindFactory(
+            'Espo\\Core\\Sms\\Sender',
+            'Espo\\Core\\Sms\\SenderFactory'
+        );
     }
 }
diff --git a/application/Espo/Core/Formula/Functions/ExtGroup/SmsGroup/SendType.php b/application/Espo/Core/Formula/Functions/ExtGroup/SmsGroup/SendType.php
new file mode 100644
index 0000000000..5c1c508dba
--- /dev/null
+++ b/application/Espo/Core/Formula/Functions/ExtGroup/SmsGroup/SendType.php
@@ -0,0 +1,96 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Formula\Functions\ExtGroup\SmsGroup;
+
+use Espo\Core\Formula\Functions\BaseFunction;
+use Espo\Core\Formula\ArgumentList;
+use Espo\Core\Sms\SmsSender;
+use Espo\Entities\Sms;
+
+use Espo\Core\Di;
+
+use Exception;
+
+class SendType extends BaseFunction implements
+
+    Di\EntityManagerAware,
+    Di\InjectableFactoryAware
+{
+    use Di\EntityManagerSetter;
+    use Di\InjectableFactorySetter;
+
+    public function process(ArgumentList $args)
+    {
+        if (count($args) < 1) {
+            $this->throwTooFewArguments(1);
+        }
+
+        $evaluatedArgs = $this->evaluate($args);
+
+        $id = $evaluatedArgs[0];
+
+        if (!$id || !is_string($id)) {
+            $this->throwBadArgumentType(1, 'string');
+        }
+
+        /** @var Sms $sms */
+        $sms = $this->entityManager->getEntity(Sms::ENTITY_TYPE, $id);
+
+        if (!$sms) {
+            $this->log("Sms '{$id}' does not exist.");
+
+            return false;
+        }
+
+        if ($sms->getStatus() === Sms::STATUS_SENT) {
+            $this->log("Can't send SMS that has 'Sent' status.");
+
+            return false;
+        }
+
+        try {
+            $this->createSender()->send($sms);
+        }
+        catch (Exception $e) {
+            $message = $e->getMessage();
+
+            $this->log("Error while sending SMS. Message: {$message}." , 'error');
+
+            return false;
+        }
+
+        return true;
+    }
+
+    private function createSender(): SmsSender
+    {
+        return $this->injectableFactory->create(SmsSender::class);
+    }
+}
diff --git a/application/Espo/Core/Sms/Sender.php b/application/Espo/Core/Sms/Sender.php
new file mode 100644
index 0000000000..ecc1d80079
--- /dev/null
+++ b/application/Espo/Core/Sms/Sender.php
@@ -0,0 +1,38 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Sms;
+
+/**
+ * An SMS sender.
+ */
+interface Sender
+{
+    public function send(Sms $sms): void;
+}
diff --git a/application/Espo/Core/Sms/SenderFactory.php b/application/Espo/Core/Sms/SenderFactory.php
new file mode 100644
index 0000000000..7a51465a02
--- /dev/null
+++ b/application/Espo/Core/Sms/SenderFactory.php
@@ -0,0 +1,74 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Sms;
+
+use Espo\Core\Binding\Factory;
+
+use Espo\Core\Utils\Config;
+use Espo\Core\Utils\Metadata;
+use Espo\Core\InjectableFactory;
+
+use RuntimeException;
+
+class SenderFactory implements Factory
+{
+    private $config;
+
+    private $metadata;
+
+    private $injectableFactory;
+
+    public function __construct(
+        Config $config,
+        Metadata $metadata,
+        InjectableFactory $injectableFactory
+    ) {
+       $this->config = $config;
+       $this->metadata = $metadata;
+       $this->injectableFactory = $injectableFactory;
+    }
+
+    public function create(): Sender
+    {
+        $provider = $this->config->get('smsProvider');
+
+        if (!$provider) {
+            throw new RuntimeException("No `smsProvider` in config.");
+        }
+
+        $className = $this->metadata->get(['app', 'smsProviders', $provider, 'senderClassName']);
+
+        if (!$className) {
+            throw new RuntimeException("No `senderClassName` for '{$provider}' provider.");
+        }
+
+        return $this->injectableFactory->create($className);
+    }
+}
diff --git a/application/Espo/Core/Sms/Sms.php b/application/Espo/Core/Sms/Sms.php
new file mode 100644
index 0000000000..471c7e1c32
--- /dev/null
+++ b/application/Espo/Core/Sms/Sms.php
@@ -0,0 +1,47 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Sms;
+
+/**
+ * An SMS message.
+ */
+interface Sms
+{
+    public function getBody(): string;
+
+    public function getFromNumber(): ?string;
+
+    public function getFromName(): ?string;
+
+    /**
+     * @return string[]
+     */
+    public function getToNumberList(): array;
+}
diff --git a/application/Espo/Core/Sms/SmsFactory.php b/application/Espo/Core/Sms/SmsFactory.php
new file mode 100644
index 0000000000..cec063c43b
--- /dev/null
+++ b/application/Espo/Core/Sms/SmsFactory.php
@@ -0,0 +1,54 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Sms;
+
+use Espo\ORM\EntityManager;
+use Espo\Entities\Sms as SmsEntity;
+
+/**
+ * Creates SMS instances.
+ */
+class SmsFactory
+{
+    private $entityManager;
+
+    public function __construct(EntityManager $entityManager)
+    {
+        $this->entityManager = $entityManager;
+    }
+
+    /**
+     * Create an SMS instance.
+     */
+    public function create(): SmsEntity
+    {
+        return $this->entityManager->getNewEntity(SmsEntity::ENTITY_TYPE);
+    }
+}
diff --git a/application/Espo/Core/Sms/SmsSender.php b/application/Espo/Core/Sms/SmsSender.php
new file mode 100644
index 0000000000..6387f62f6a
--- /dev/null
+++ b/application/Espo/Core/Sms/SmsSender.php
@@ -0,0 +1,60 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Sms;
+
+use Espo\Entities\Sms as SmsEntity;
+
+use Espo\Core\Utils\Config;
+
+class SmsSender
+{
+    private $sender;
+
+    private $config;
+
+    public function __construct(Sender $sender, Config $config)
+    {
+        $this->sender = $sender;
+        $this->config = $config;
+    }
+
+    public function send(SmsEntity $sms): void
+    {
+        $systemFromNumber = $this->config->get('outboundSmsFromNumber');
+
+        if ($sms->getFromNumber() === null && $systemFromNumber) {
+            $sms->setFromNumber($systemFromNumber);
+        }
+
+        $this->sender->send($sms);
+
+        $sms->setAsSent();
+    }
+}
diff --git a/application/Espo/Core/Utils/Database/Orm/Relations/SmsPhoneNumber.php b/application/Espo/Core/Utils/Database/Orm/Relations/SmsPhoneNumber.php
new file mode 100644
index 0000000000..73550be8da
--- /dev/null
+++ b/application/Espo/Core/Utils/Database/Orm/Relations/SmsPhoneNumber.php
@@ -0,0 +1,57 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Core\Utils\Database\Orm\Relations;
+
+use Espo\Core\Utils\Util;
+
+class SmsPhoneNumber extends HasMany
+{
+    protected function load($linkName, $entityName)
+    {
+        $parentRelation = parent::load($linkName, $entityName);
+
+        $foreignEntityName = $this->getForeignEntityName();
+
+        $relation = [
+            $entityName => [
+                'relations' => [
+                    $linkName => [
+                        'midKeys' => [
+                            lcfirst($entityName) . 'Id',
+                            lcfirst($foreignEntityName) . 'Id',
+                        ],
+                    ],
+                ],
+            ],
+        ];
+
+        return Util::merge($parentRelation, $relation);
+    }
+}
diff --git a/application/Espo/Entities/Sms.php b/application/Espo/Entities/Sms.php
new file mode 100644
index 0000000000..6038adce7d
--- /dev/null
+++ b/application/Espo/Entities/Sms.php
@@ -0,0 +1,134 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Entities;
+
+use Espo\Core\ORM\Entity;
+use Espo\Core\Sms\Sms as SmsInterface;
+use Espo\Core\Field\DateTime;
+
+use Espo\Repositories\Sms as SmsRepository;
+
+class Sms extends Entity implements SmsInterface
+{
+    public const ENTITY_TYPE = 'Sms';
+
+    public const STATUS_ARCHIVED = 'Archived';
+
+    public const STATUS_SENT = 'Sent';
+
+    public const STATUS_SENDING = 'Sending';
+
+    public const STATUS_DRAFT = 'Draft';
+
+    public function getDateSent(): ?DateTime
+    {
+        return $this->getValueObject('dateTime');
+    }
+
+    public function getCreatedAt(): ?DateTime
+    {
+        return $this->getValueObject('createdAt');
+    }
+
+    public function getBody(): string
+    {
+        return $this->get('body') ?? '';
+    }
+
+    public function getStatus(): ?string
+    {
+        return $this->get('status');
+    }
+
+    public function setBody(?string $body): void
+    {
+        $this->set('body', $body);
+    }
+
+    public function setFromNumber(?string $number): void
+    {
+        $this->set('from', $number);
+    }
+
+    public function addToNumber(string $number): void
+    {
+        $list = $this->getToNumberList();
+
+        $list[] = $number;
+
+        $this->set('to', implode(';', $list));
+    }
+
+    public function getFromNumber(): ?string
+    {
+        if (!$this->hasInContainer('from') && !$this->isNew()) {
+            $this->getSmsRepository()->loadFromField($this);
+        }
+
+        return $this->get('from');
+    }
+
+    public function getFromName(): ?string
+    {
+        return $this->get('fromName');
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getToNumberList(): array
+    {
+        if (!$this->hasInContainer('to') && !$this->isNew()) {
+            $this->getSmsRepository()->loadToField($this);
+        }
+
+        $value = $this->get('to');
+
+        if (!$value) {
+            return [];
+        }
+
+        return explode(';', $value);
+    }
+
+    public function setAsSent(): void
+    {
+        $this->set('status', self::STATUS_SENT);
+
+        if (!$this->get('dateSent')) {
+            $this->set('dateSent', DateTime::createNow()->getString());
+        }
+    }
+
+    private function getSmsRepository(): SmsRepository
+    {
+        return $this->entityManager->getRepository(self::ENTITY_TYPE);
+    }
+}
diff --git a/application/Espo/Hooks/Sms/Numbers.php b/application/Espo/Hooks/Sms/Numbers.php
new file mode 100644
index 0000000000..c36ecef705
--- /dev/null
+++ b/application/Espo/Hooks/Sms/Numbers.php
@@ -0,0 +1,111 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Hooks\Sms;
+
+use Espo\ORM\EntityManager;
+use Espo\Entities\Sms;
+use Espo\Entities\PhoneNumber;
+use Espo\Repositories\PhoneNumber as PhoneNumberRepository;
+
+use Espo\ORM\Entity;
+
+class Numbers
+{
+    private $entityManager;
+
+    public function __construct(EntityManager $entityManager)
+    {
+        $this->entityManager = $entityManager;
+    }
+
+    public function beforeSave(Entity $entity): void
+    {
+        $this->processNumbers($entity);
+    }
+
+    private function processNumbers(Sms $entity): void
+    {
+        if ($entity->has('from')) {
+            $this->processFrom($entity);
+        }
+
+        if ($entity->has('to')) {
+            $this->processTo($entity);
+        }
+    }
+
+    private function processFrom(Sms $entity): void
+    {
+        $from = $entity->get('from');
+
+        $entity->set('fromPhoneNumberId', null);
+        $entity->set('fromEmailAddressName', null);
+
+        if (!$from) {
+            return;
+        }
+
+        $numberIds = $this->getPhoneNumberRepository()->getIds([$from]);
+
+        if (!count($numberIds)) {
+            return;
+        }
+
+        $entity->set('fromEmailAddressId', $numberIds[0]);
+        $entity->set('fromEmailAddressName', $from);
+    }
+
+    private function processTo(Sms $entity): void
+    {
+        $entity->setLinkMultipleIdList('toPhoneNumbers', []);
+
+        $to = $entity->get('to');
+
+        if ($to === null || !$to) {
+            return;
+        }
+
+        $numberList = array_map(
+            function (string $item): string {
+                return trim($item);
+            },
+            explode(';', $to)
+        );
+
+        $numberIds = $this->getPhoneNumberRepository()->getIds($numberList);
+
+        $entity->setLinkMultipleIdList('toPhoneNumbers', $numberIds);
+    }
+
+    private function getPhoneNumberRepository(): PhoneNumberRepository
+    {
+        return $this->entityManager->getRepository(PhoneNumber::ENTITY_TYPE);
+    }
+}
diff --git a/application/Espo/Repositories/Sms.php b/application/Espo/Repositories/Sms.php
new file mode 100644
index 0000000000..c13f15ede9
--- /dev/null
+++ b/application/Espo/Repositories/Sms.php
@@ -0,0 +1,84 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Repositories;
+
+use Espo\Entities\Sms as SmsEntity;
+use Espo\Entities\PhoneNumber;
+
+use Espo\Core\Repositories\Database;
+
+class Sms extends Database
+{
+    public function loadFromField(SmsEntity $entity): void
+    {
+        if ($entity->get('fromPhoneNumberName')) {
+            $entity->set('from', $entity->get('fromPhoneNumberName'));
+
+            return;
+        }
+
+        $numberId = $entity->get('fromPhoneNumberId');
+
+        if ($numberId) {
+            $phoneNumber = $this->entityManager
+                ->getRepository(PhoneNumber::ENTITY_TYPE)
+                ->getById($numberId);
+
+            if ($phoneNumber) {
+                $entity->set('from', $phoneNumber->get('name'));
+
+                return;
+            }
+        }
+
+        $entity->set('from', null);
+    }
+
+    public function loadToField(SmsEntity $entity): void
+    {
+        $entity->loadLinkMultipleField('toPhoneNumbers');
+
+        $names = $entity->get('toPhoneNumbersNames');
+
+        if (empty($names)) {
+            $entity->set('to', null);
+
+            return;
+        }
+
+        $list = [];
+
+        foreach ($names as $address) {
+            $list[] = $address;
+        }
+
+        $entity->set('to', implode(';', $list));
+    }
+}
diff --git a/application/Espo/Resources/defaults/systemConfig.php b/application/Espo/Resources/defaults/systemConfig.php
index 3e1d2b76bf..bc92f1555e 100644
--- a/application/Espo/Resources/defaults/systemConfig.php
+++ b/application/Espo/Resources/defaults/systemConfig.php
@@ -205,6 +205,7 @@ return [
         'passwordRecoveryRequestDelay',
         'thumbImageCacheDisabled',
         'emailReminderPortionSize',
+        'outboundSmsFromNumber',
         'latestVersion',
     ],
     'superAdminItems' => [
diff --git a/application/Espo/Resources/i18n/en_US/Admin.json b/application/Espo/Resources/i18n/en_US/Admin.json
index a2efbcec90..dbd24b2701 100644
--- a/application/Espo/Resources/i18n/en_US/Admin.json
+++ b/application/Espo/Resources/i18n/en_US/Admin.json
@@ -5,6 +5,7 @@
         "System": "System",
         "Users": "Users",
         "Email": "Email",
+        "Messaging": "Messaging",
         "Data": "Data",
         "Customization": "Customization",
         "Available Fields": "Available Fields",
@@ -278,6 +279,7 @@
         "dashboardTemplates": "Deploy dashboards to users.",
         "layoutSets": "Collections of layouts that can be assigned to teams & portals.",
         "jobsSettings": "Job processing settings. Jobs execute tasks in the background.",
+        "sms": "SMS settings.",
         "pdfTemplates": "Templates for printing to PDF."
     },
     "keywords": {
diff --git a/application/Espo/Resources/i18n/en_US/Settings.json b/application/Espo/Resources/i18n/en_US/Settings.json
index fa652ed41a..542f5587d4 100644
--- a/application/Espo/Resources/i18n/en_US/Settings.json
+++ b/application/Espo/Resources/i18n/en_US/Settings.json
@@ -13,6 +13,8 @@
         "currencyList": "Currency List",
         "language": "Language",
         "companyLogo": "Company Logo",
+        "smsProvider": "SMS Provider",
+        "outboundSmsFromNumber": "SMS From Number",
         "smtpServer": "Server",
         "smtpPort": "Port",
         "smtpAuth": "Auth",
@@ -155,7 +157,8 @@
         },
         "auth2FAMethodList": {
             "Totp": "TOTP",
-            "Email": "Email"
+            "Email": "Email",
+            "Sms": "SMS"
         }
     },
     "tooltips": {
diff --git a/application/Espo/Resources/i18n/en_US/User.json b/application/Espo/Resources/i18n/en_US/User.json
index e43cdf74b0..ca4aad54f3 100644
--- a/application/Espo/Resources/i18n/en_US/User.json
+++ b/application/Espo/Resources/i18n/en_US/User.json
@@ -109,8 +109,11 @@
         "userNameExists": "User Name already exists",
         "wrongCode": "Wrong code",
         "codeIsRequired": "Code is required",
+        "yourAuthenticationCode": "Your authentication code: {code}.",
+        "choose2FaSmsPhoneNumber": "Select a phone number that will be used for 2FA.",
         "choose2FaEmailAddress": "Select an email address that will be used for 2FA. It's highly recommended to use a non-primary email address.",
         "enterCodeSentInEmail": "Enter the code sent to your email address.",
+        "enterCodeSentBySms": "Enter the code sent by SMS to your phone number.",
         "enterTotpCode": "Enter a code from your authenticator app.",
         "verifyTotpCode": "Scan the QR-code with your mobile authenticator app. If you have a trouble with scanning, you can enter the secret manually. After that you will see a 6-digit code in your application. Enter this code in the field below.",
         "generateAndSendNewPassword": "A new password will be generated and sent to the user's email address.",
diff --git a/application/Espo/Resources/layouts/Settings/sms.json b/application/Espo/Resources/layouts/Settings/sms.json
new file mode 100644
index 0000000000..240f2dadbf
--- /dev/null
+++ b/application/Espo/Resources/layouts/Settings/sms.json
@@ -0,0 +1,8 @@
+[
+    {
+        "rows": [
+            [{"name": "smsProvider"}, false],
+            [{"name": "outboundSmsFromNumber"}, false]
+        ]
+    }
+]
diff --git a/application/Espo/Resources/metadata/app/adminPanel.json b/application/Espo/Resources/metadata/app/adminPanel.json
index be96e5cdf1..cda71f308b 100644
--- a/application/Espo/Resources/metadata/app/adminPanel.json
+++ b/application/Espo/Resources/metadata/app/adminPanel.json
@@ -169,7 +169,7 @@
         "order": 10
     },
     "email":{
-        "label": "Email",
+        "label": "Messaging",
         "itemList": [
             {
                 "url": "#Admin/outboundEmails",
@@ -208,6 +208,13 @@
                 "label": "Email Templates",
                 "iconClass": "fas fa-envelope-square",
                 "description": "emailTemplates"
+            },
+            {
+                "url": "#Admin/sms",
+                "label": "SMS",
+                "iconClass": "fas fa-paper-plane",
+                "description": "sms",
+                "recordView": "views/admin/sms"
             }
         ],
         "order": 15
diff --git a/application/Espo/Resources/metadata/app/authentication2FAMethods.json b/application/Espo/Resources/metadata/app/authentication2FAMethods.json
index 328293de1a..1e804f89d2 100644
--- a/application/Espo/Resources/metadata/app/authentication2FAMethods.json
+++ b/application/Espo/Resources/metadata/app/authentication2FAMethods.json
@@ -14,5 +14,13 @@
         "userApplyView": "views/user-security/modals/two-factor-email",
         "loginClassName": "Espo\\Core\\Authentication\\TwoFactor\\Email\\EmailLogin",
         "userSetupClassName": "Espo\\Core\\Authentication\\TwoFactor\\Email\\EmailUserSetup"
+    },
+    "Sms": {
+        "settings": {
+            "isAvailable": true
+        },
+        "userApplyView": "views/user-security/modals/two-factor-sms",
+        "loginClassName": "Espo\\Core\\Authentication\\TwoFactor\\Sms\\SmsLogin",
+        "userSetupClassName": "Espo\\Core\\Authentication\\TwoFactor\\Sms\\SmsUserSetup"
     }
 }
diff --git a/application/Espo/Resources/metadata/app/config.json b/application/Espo/Resources/metadata/app/config.json
index 087d053a19..73a361c5f5 100644
--- a/application/Espo/Resources/metadata/app/config.json
+++ b/application/Espo/Resources/metadata/app/config.json
@@ -15,6 +15,9 @@
     "params": {
         "awsS3Storage": {
             "level": "system"
+        },
+        "smsProvider": {
+            "level": "admin"
         }
     }
 }
diff --git a/application/Espo/Resources/metadata/app/formula.json b/application/Espo/Resources/metadata/app/formula.json
index 69ea90f4df..028031ca59 100644
--- a/application/Espo/Resources/metadata/app/formula.json
+++ b/application/Espo/Resources/metadata/app/formula.json
@@ -378,6 +378,11 @@
             "insertText": "ext\\email\\send(EMAIL_ID)",
             "returnType": "bool"
         },
+        {
+            "name": "ext\\sms\\send",
+            "insertText": "ext\\sms\\send(SMS_ID)",
+            "returnType": "bool"
+        },
         {
             "name": "ext\\email\\applyTemplate",
             "insertText": "ext\\email\\applyTemplate(EMAIL_ID, EMAIL_TEMPLATE_ID)"
diff --git a/application/Espo/Resources/metadata/app/metadata.json b/application/Espo/Resources/metadata/app/metadata.json
index c848a7d0cc..eb2dba42eb 100644
--- a/application/Espo/Resources/metadata/app/metadata.json
+++ b/application/Espo/Resources/metadata/app/metadata.json
@@ -25,6 +25,7 @@
         ["app", "webSocket", "messagers"],
         ["app", "config"],
         ["app", "rebuild"],
+        ["app", "smsProviders", "__ANY__", "senderClassName"],
         ["selectDefs"],
         ["recordDefs"],
         ["pdfDefs"],
diff --git a/application/Espo/Resources/metadata/app/smsProviders.json b/application/Espo/Resources/metadata/app/smsProviders.json
new file mode 100644
index 0000000000..0db3279e44
--- /dev/null
+++ b/application/Espo/Resources/metadata/app/smsProviders.json
@@ -0,0 +1,3 @@
+{
+
+}
diff --git a/application/Espo/Resources/metadata/entityDefs/Settings.json b/application/Espo/Resources/metadata/entityDefs/Settings.json
index 910216587a..e77469c488 100644
--- a/application/Espo/Resources/metadata/entityDefs/Settings.json
+++ b/application/Espo/Resources/metadata/entityDefs/Settings.json
@@ -635,6 +635,14 @@
         },
         "awsS3Storage": {
             "type": "jsonObject"
+        },
+        "outboundSmsFromNumber": {
+            "type": "varchar",
+            "trim": true
+        },
+        "smsProvider": {
+            "type": "enum",
+            "view": "views/settings/fields/sms-provider"
         }
     }
 }
diff --git a/application/Espo/Resources/metadata/entityDefs/Sms.json b/application/Espo/Resources/metadata/entityDefs/Sms.json
new file mode 100644
index 0000000000..9c25ebaac7
--- /dev/null
+++ b/application/Espo/Resources/metadata/entityDefs/Sms.json
@@ -0,0 +1,147 @@
+{
+    "fields": {
+        "from": {
+            "type": "varchar",
+            "notStorable": true,
+            "required": true,
+            "textFilterDisabled": true
+        },
+        "fromName": {
+            "type": "varchar"
+        },
+        "to": {
+            "type": "varchar",
+            "notStorable": true,
+            "required": true,
+            "textFilterDisabled": true
+        },
+        "fromPhoneNumber": {
+            "type": "link",
+            "textFilterDisabled": true
+        },
+        "toPhoneNumbers": {
+            "type": "linkMultiple"
+        },
+        "body": {
+            "type": "text"
+        },
+        "status": {
+            "type": "enum",
+            "options": ["Draft", "Sending", "Sent", "Archived", "Failed"],
+            "default": "Archived",
+            "clientReadOnly": true,
+            "style": {
+                "Draft": "warning",
+                "Failed": "danger",
+                "Sending": "warning"
+            }
+        },
+        "parent": {
+            "type": "linkParent"
+        },
+        "dateSent": {
+            "type": "datetime"
+        },
+        "createdAt": {
+            "type": "datetime",
+            "readOnly": true
+        },
+        "modifiedAt": {
+            "type": "datetime",
+            "readOnly": true
+        },
+        "createdBy": {
+            "type": "link",
+            "readOnly": true,
+            "view": "views/fields/user"
+        },
+        "modifiedBy": {
+            "type": "link",
+            "readOnly": true,
+            "view": "views/fields/user"
+        },
+        "replied": {
+            "type": "link",
+            "noJoin": true,
+            "readOnly": true,
+            "view": "views/email/fields/replied"
+        },
+        "replies": {
+            "type": "linkMultiple",
+            "readOnly": true,
+            "orderBy": "dateSent",
+            "view": "views/email/fields/replies"
+        },
+        "teams": {
+            "type": "linkMultiple",
+            "view": "views/fields/teams"
+        }
+    },
+    "links": {
+        "createdBy": {
+            "type": "belongsTo",
+            "entity": "User"
+        },
+        "modifiedBy": {
+            "type": "belongsTo",
+            "entity": "User"
+        },
+        "teams": {
+            "type": "hasMany",
+            "entity": "Team",
+            "relationName": "entityTeam"
+        },
+        "parent": {
+            "type": "belongsToParent",
+            "entityList": [
+                "Account",
+                "Contact",
+                "Lead",
+                "Opportunity"
+            ],
+            "foreign": "emails"
+        },
+        "replied": {
+            "type": "belongsTo",
+            "entity": "Sms",
+            "foreign": "replies",
+            "foreignName": "id"
+        },
+        "replies": {
+            "type": "hasMany",
+            "entity": "Sms",
+            "foreign": "replied"
+        },
+        "fromPhoneNumber": {
+            "type": "belongsTo",
+            "entity": "PhoneNumber"
+        },
+        "toPhoneNumbers": {
+            "type": "hasMany",
+            "entity": "PhoneNumber",
+            "relationName": "smsPhoneNumber",
+            "conditions": {
+                "addressType": "to"
+            },
+            "additionalColumns": {
+                "addressType": {
+                    "type": "varchar",
+                    "len": "4"
+                }
+            }
+        }
+    },
+    "collection": {
+        "orderBy": "dateSent",
+        "order": "desc",
+        "textFilterFields": ["name", "body"]
+    },
+    "indexes": {
+        "dateSent": {
+            "columns": ["dateSent", "deleted"]
+        },
+        "dateSentStatus": {
+            "columns": ["dateSent", "status", "deleted"]
+        }
+    }
+}
diff --git a/application/Espo/Services/TwoFactorSms.php b/application/Espo/Services/TwoFactorSms.php
new file mode 100644
index 0000000000..08af257c45
--- /dev/null
+++ b/application/Espo/Services/TwoFactorSms.php
@@ -0,0 +1,90 @@
+<?php
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+namespace Espo\Services;
+
+use Espo\Core\Exceptions\Forbidden;
+use Espo\Core\Exceptions\NotFound;
+
+use Espo\Core\Utils\Config;
+use Espo\Core\Authentication\TwoFactor\Sms\Util;
+
+use Espo\ORM\EntityManager;
+
+use Espo\Entities\User;
+
+class TwoFactorSms
+{
+    private $util;
+
+    private $user;
+
+    private $entityManager;
+
+    private $config;
+
+    public function __construct(Util $util, User $user, EntityManager $entityManager, Config $config)
+    {
+        $this->util = $util;
+        $this->user = $user;
+        $this->entityManager = $entityManager;
+        $this->config = $config;
+    }
+
+    public function sendCode(string $userId, string $phoneNumber): void
+    {
+        if (!$this->user->isAdmin() && $userId !== $this->user->getId()) {
+            throw new Forbidden();
+        }
+
+        $this->checkAllowed();
+
+        $user = $this->entityManager->getEntity(User::ENTITY_TYPE, $userId);
+
+        if (!$user) {
+            throw new NotFound();
+        }
+
+        $this->util->sendCode($user, $phoneNumber);
+        $this->util->storePhoneNumber($user, $phoneNumber);
+    }
+
+    private function checkAllowed(): void
+    {
+        if (!$this->config->get('auth2FA')) {
+            throw new Forbidden("2FA is not enabled.");
+        }
+
+        $methodList = $this->config->get('auth2FAMethodList') ?? [];
+
+        if (!in_array('Sms', $methodList)) {
+            throw new Forbidden("Sms 2FA is not allowed.");
+        }
+    }
+}
diff --git a/client/res/templates/user-security/modals/two-factor-sms.tpl b/client/res/templates/user-security/modals/two-factor-sms.tpl
new file mode 100644
index 0000000000..138ca89731
--- /dev/null
+++ b/client/res/templates/user-security/modals/two-factor-sms.tpl
@@ -0,0 +1,15 @@
+<div class="panel no-side-margin">
+    <div class="panel-body">
+        <p class="p-info">
+            {{translate 'choose2FaSmsPhoneNumber' category='messages' scope='User'}}
+        </p>
+        <p class="p-button">
+            <button class="btn btn-default" data-action="sendCode">{{translate 'Send Code' scope='User'}}</button>
+        </p>
+        <p class="p-info-after hidden">
+            {{translate 'enterCodeSentBySms' category='messages' scope='User'}}
+        </p>
+    </div>
+</div>
+
+<div class="record">{{{record}}}</div>
diff --git a/client/src/views/admin/sms.js b/client/src/views/admin/sms.js
new file mode 100644
index 0000000000..e365aa3dcd
--- /dev/null
+++ b/client/src/views/admin/sms.js
@@ -0,0 +1,36 @@
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+define('views/admin/sms', 'views/settings/record/edit', function (Dep) {
+
+    return Dep.extend({
+
+        layoutName: 'sms',
+
+    });
+});
diff --git a/client/src/views/settings/fields/sms-provider.js b/client/src/views/settings/fields/sms-provider.js
new file mode 100644
index 0000000000..3d5e0bb884
--- /dev/null
+++ b/client/src/views/settings/fields/sms-provider.js
@@ -0,0 +1,39 @@
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+define('views/settings/fields/sms-provider', 'views/fields/enum', function (Dep) {
+
+    return Dep.extend({
+
+        setupOptions: function () {
+            this.params.options = Object.keys(
+                this.getMetadata().get(['app', 'smsProviders']) || {}
+            );
+        },
+    });
+});
diff --git a/client/src/views/user-security/modals/two-factor-sms.js b/client/src/views/user-security/modals/two-factor-sms.js
new file mode 100644
index 0000000000..e8b0f15ad7
--- /dev/null
+++ b/client/src/views/user-security/modals/two-factor-sms.js
@@ -0,0 +1,192 @@
+/************************************************************************
+ * This file is part of EspoCRM.
+ *
+ * EspoCRM - Open Source CRM application.
+ * Copyright (C) 2014-2021 Yurii Kuznietsov, Taras Machyshyn, Oleksii Avramenko
+ * Website: https://www.espocrm.com
+ *
+ * EspoCRM is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * EspoCRM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with EspoCRM. If not, see http://www.gnu.org/licenses/.
+ *
+ * The interactive user interfaces in modified source and object code versions
+ * of this program must display Appropriate Legal Notices, as required under
+ * Section 5 of the GNU General Public License version 3.
+ *
+ * In accordance with Section 7(b) of the GNU General Public License version 3,
+ * these Appropriate Legal Notices must retain the display of the "EspoCRM" word.
+ ************************************************************************/
+
+define('views/user-security/modals/two-factor-sms',
+    ['views/modal', 'model'],
+    function (Dep, Model) {
+
+    return Dep.extend({
+
+        template: 'user-security/modals/two-factor-sms',
+
+        className: 'dialog dialog-record',
+
+        events: {
+            'click [data-action="sendCode"]': function () {
+                this.actionSendCode();
+            },
+        },
+
+        setup: function () {
+            this.buttonList = [
+                {
+                    name: 'apply',
+                    label: 'Apply',
+                    style: 'danger',
+                    hidden: true,
+                },
+                {
+                    name: 'cancel',
+                    label: 'Cancel',
+                }
+            ];
+
+            this.headerHtml = false;
+
+            let codeLength = this.getConfig().get('auth2FASmsCodeLength') || 7;
+
+            let model = new Model();
+
+            model.name = 'UserSecurity';
+
+            model.set('phoneNumber', null);
+
+            model.setDefs({
+                fields: {
+                    'code': {
+                        type: 'varchar',
+                        required: true,
+                        maxLength: codeLength,
+                    },
+                    'phoneNumber': {
+                        type: 'enum',
+                        required: true,
+                    },
+                }
+            });
+
+            this.internalModel = model;
+
+            this.wait(
+                Espo.Ajax
+                    .postRequest('UserSecurity/action/getTwoFactorUserSetupData', {
+                        id: this.model.id,
+                        password: this.model.get('password'),
+                        auth2FAMethod: this.model.get('auth2FAMethod'),
+                        reset: this.options.reset,
+                    })
+                    .then(data => {
+                        this.phoneNumberList = data.phoneNumberList;
+
+                        this.createView('record', 'views/record/edit-for-modal', {
+                            scope: 'None',
+                            el: this.getSelector() + ' .record',
+                            model: model,
+                            detailLayout: [
+                                {
+                                    rows: [
+                                        [
+                                            {
+                                                name: 'phoneNumber',
+                                                labelText: this.translate('phoneNumber', 'fields', 'User'),
+                                            },
+                                            false
+                                        ],
+                                        [
+                                            {
+                                                name: 'code',
+                                                labelText: this.translate('Code', 'labels', 'User'),
+                                            },
+                                            false
+                                        ],
+                                    ]
+                                }
+                            ],
+                        }, view => {
+                            view.setFieldOptionList('phoneNumber', this.phoneNumberList);
+
+                            if (this.phoneNumberList.length) {
+                                model.set('phoneNumber', this.phoneNumberList[0]);
+                            }
+
+                            view.hideField('code');
+                        });
+                    })
+            );
+        },
+
+        afterRender: function () {
+            this.$sendCode = this.$el.find('[data-action="sendCode"]');
+
+            this.$pInfo = this.$el.find('p.p-info');
+            this.$pButton = this.$el.find('p.p-button');
+            this.$pInfoAfter = this.$el.find('p.p-info-after');
+        },
+
+        actionSendCode: function () {
+            this.$sendCode.attr('disabled', 'disabled').addClass('disabled');
+
+            Espo.Ajax
+                .postRequest('TwoFactorSms/action/sendCode', {
+                    id: this.model.id,
+                    phoneNumber: this.internalModel.get('phoneNumber'),
+                })
+                .then(() => {
+                    this.showButton('apply');
+
+                    this.$pInfo.addClass('hidden');
+                    this.$pButton.addClass('hidden');
+                    this.$pInfoAfter.removeClass('hidden');
+
+                    this.getView('record').setFieldReadOnly('phoneNumber');
+                    this.getView('record').showField('code');
+                })
+                .catch(() => {
+                    this.$sendCode.removeAttr('disabled').removeClass('disabled');
+                });
+        },
+
+        actionApply: function () {
+            let data = this.getView('record').processFetch();
+
+            if (!data) {
+                return;
+            }
+
+            this.model.set('code', data.code);
+
+            this.hideButton('apply');
+            this.hideButton('cancel');
+
+            Espo.Ui.notify(this.translate('pleaseWait', 'messages'));
+
+            this.model
+                .save()
+                .then(() => {
+                    Espo.Ui.notify(false);
+
+                    this.trigger('done');
+                })
+                .catch(() => {
+                    this.showButton('apply');
+                    this.showButton('cancel');
+                });
+        },
+
+    });
+});