diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -3423,6 +3423,7 @@
     'PhabricatorMailReceiverTestCase' => 'applications/metamta/receiver/__tests__/PhabricatorMailReceiverTestCase.php',
     'PhabricatorMailReplyHandler' => 'applications/metamta/replyhandler/PhabricatorMailReplyHandler.php',
     'PhabricatorMailRoutingRule' => 'applications/metamta/constants/PhabricatorMailRoutingRule.php',
+    'PhabricatorMailSMSMessage' => 'applications/metamta/message/PhabricatorMailSMSMessage.php',
     'PhabricatorMailSMTPAdapter' => 'applications/metamta/adapter/PhabricatorMailSMTPAdapter.php',
     'PhabricatorMailSendGridAdapter' => 'applications/metamta/adapter/PhabricatorMailSendGridAdapter.php',
     'PhabricatorMailSendmailAdapter' => 'applications/metamta/adapter/PhabricatorMailSendmailAdapter.php',
@@ -3430,6 +3431,7 @@
     'PhabricatorMailStamp' => 'applications/metamta/stamp/PhabricatorMailStamp.php',
     'PhabricatorMailTarget' => 'applications/metamta/replyhandler/PhabricatorMailTarget.php',
     'PhabricatorMailTestAdapter' => 'applications/metamta/adapter/PhabricatorMailTestAdapter.php',
+    'PhabricatorMailTwilioAdapter' => 'applications/metamta/adapter/PhabricatorMailTwilioAdapter.php',
     'PhabricatorMailUtil' => 'applications/metamta/util/PhabricatorMailUtil.php',
     'PhabricatorMainMenuBarExtension' => 'view/page/menu/PhabricatorMainMenuBarExtension.php',
     'PhabricatorMainMenuSearchView' => 'view/page/menu/PhabricatorMainMenuSearchView.php',
@@ -3851,6 +3853,7 @@
     'PhabricatorPholioApplication' => 'applications/pholio/application/PhabricatorPholioApplication.php',
     'PhabricatorPholioConfigOptions' => 'applications/pholio/config/PhabricatorPholioConfigOptions.php',
     'PhabricatorPholioMockTestDataGenerator' => 'applications/pholio/lipsum/PhabricatorPholioMockTestDataGenerator.php',
+    'PhabricatorPhoneNumber' => 'applications/metamta/message/PhabricatorPhoneNumber.php',
     'PhabricatorPhortuneApplication' => 'applications/phortune/application/PhabricatorPhortuneApplication.php',
     'PhabricatorPhortuneContentSource' => 'applications/phortune/contentsource/PhabricatorPhortuneContentSource.php',
     'PhabricatorPhortuneManagementInvoiceWorkflow' => 'applications/phortune/management/PhabricatorPhortuneManagementInvoiceWorkflow.php',
@@ -9257,6 +9260,7 @@
     'PhabricatorMailReceiverTestCase' => 'PhabricatorTestCase',
     'PhabricatorMailReplyHandler' => 'Phobject',
     'PhabricatorMailRoutingRule' => 'Phobject',
+    'PhabricatorMailSMSMessage' => 'PhabricatorMailExternalMessage',
     'PhabricatorMailSMTPAdapter' => 'PhabricatorMailAdapter',
     'PhabricatorMailSendGridAdapter' => 'PhabricatorMailAdapter',
     'PhabricatorMailSendmailAdapter' => 'PhabricatorMailAdapter',
@@ -9264,6 +9268,7 @@
     'PhabricatorMailStamp' => 'Phobject',
     'PhabricatorMailTarget' => 'Phobject',
     'PhabricatorMailTestAdapter' => 'PhabricatorMailAdapter',
+    'PhabricatorMailTwilioAdapter' => 'PhabricatorMailAdapter',
     'PhabricatorMailUtil' => 'Phobject',
     'PhabricatorMainMenuBarExtension' => 'Phobject',
     'PhabricatorMainMenuSearchView' => 'AphrontView',
@@ -9768,6 +9773,7 @@
     'PhabricatorPholioApplication' => 'PhabricatorApplication',
     'PhabricatorPholioConfigOptions' => 'PhabricatorApplicationConfigOptions',
     'PhabricatorPholioMockTestDataGenerator' => 'PhabricatorTestDataGenerator',
+    'PhabricatorPhoneNumber' => 'Phobject',
     'PhabricatorPhortuneApplication' => 'PhabricatorApplication',
     'PhabricatorPhortuneContentSource' => 'PhabricatorContentSource',
     'PhabricatorPhortuneManagementInvoiceWorkflow' => 'PhabricatorPhortuneManagementWorkflow',
diff --git a/src/applications/metamta/adapter/PhabricatorMailTwilioAdapter.php b/src/applications/metamta/adapter/PhabricatorMailTwilioAdapter.php
new file mode 100644
--- /dev/null
+++ b/src/applications/metamta/adapter/PhabricatorMailTwilioAdapter.php
@@ -0,0 +1,61 @@
+<?php
+
+final class PhabricatorMailTwilioAdapter
+  extends PhabricatorMailAdapter {
+
+  const ADAPTERTYPE = 'twilio';
+
+  public function getSupportedMessageTypes() {
+    return array(
+      PhabricatorMailSMSMessage::MESSAGETYPE,
+    );
+  }
+
+  protected function validateOptions(array $options) {
+    PhutilTypeSpec::checkMap(
+      $options,
+      array(
+        'account-sid' => 'string',
+        'auth-token' => 'string',
+        'from-number' => 'string',
+      ));
+
+    // Construct an object from the "from-number" to validate it.
+    $number = new PhabricatorPhoneNumber($options['from-number']);
+  }
+
+  public function newDefaultOptions() {
+    return array(
+      'account-sid' => null,
+      'auth-token' => null,
+      'from-number' => null,
+    );
+  }
+
+  public function sendMessage(PhabricatorMailExternalMessage $message) {
+    $account_sid = $this->getOption('account-sid');
+
+    $auth_token = $this->getOption('auth-token');
+    $auth_token = new PhutilOpaqueEnvelope($auth_token);
+
+    $from_number = $this->getOption('from-number');
+    $from_number = new PhabricatorPhoneNumber($from_number);
+
+    $to_number = $message->getToNumber();
+    $text_body = $message->getTextBody();
+
+    $parameters = array(
+      'From' => $from_number->toE164(),
+      'To' => $to_number->toE164(),
+      'Body' => $text_body,
+    );
+
+    $result = id(new PhabricatorTwilioFuture())
+      ->setAccountSID($account_sid)
+      ->setAuthToken($auth_token)
+      ->setMethod('Messages.json', $parameters)
+      ->setTimeout(60)
+      ->resolve();
+  }
+
+}
diff --git a/src/applications/metamta/future/PhabricatorTwilioFuture.php b/src/applications/metamta/future/PhabricatorTwilioFuture.php
--- a/src/applications/metamta/future/PhabricatorTwilioFuture.php
+++ b/src/applications/metamta/future/PhabricatorTwilioFuture.php
@@ -7,6 +7,7 @@
   private $authToken;
   private $method;
   private $parameters;
+  private $timeout;
 
   public function __construct() {
     parent::__construct(null);
@@ -28,6 +29,15 @@
     return $this;
   }
 
+  public function setTimeout($timeout) {
+    $this->timeout = $timeout;
+    return $this;
+  }
+
+  public function getTimeout() {
+    return $this->timeout;
+  }
+
   protected function getProxiedFuture() {
     if (!$this->future) {
       if ($this->accountSID === null) {
@@ -58,6 +68,11 @@
         ->setMethod('POST')
         ->addHeader('Accept', 'application/json');
 
+      $timeout = $this->getTimeout();
+      if ($timeout) {
+        $future->setTimeout($timeout);
+      }
+
       $this->future = $future;
     }
 
diff --git a/src/applications/metamta/message/PhabricatorMailSMSMessage.php b/src/applications/metamta/message/PhabricatorMailSMSMessage.php
new file mode 100644
--- /dev/null
+++ b/src/applications/metamta/message/PhabricatorMailSMSMessage.php
@@ -0,0 +1,29 @@
+<?php
+
+final class PhabricatorMailSMSMessage
+  extends PhabricatorMailExternalMessage {
+
+  const MESSAGETYPE = 'sms';
+
+  private $toNumber;
+  private $textBody;
+
+  public function setToNumber(PhabricatorPhoneNumber $to_number) {
+    $this->toNumber = $to_number;
+    return $this;
+  }
+
+  public function getToNumber() {
+    return $this->toNumber;
+  }
+
+  public function setTextBody($text_body) {
+    $this->textBody = $text_body;
+    return $this;
+  }
+
+  public function getTextBody() {
+    return $this->textBody;
+  }
+
+}
diff --git a/src/applications/metamta/message/PhabricatorPhoneNumber.php b/src/applications/metamta/message/PhabricatorPhoneNumber.php
new file mode 100644
--- /dev/null
+++ b/src/applications/metamta/message/PhabricatorPhoneNumber.php
@@ -0,0 +1,25 @@
+<?php
+
+final class PhabricatorPhoneNumber
+  extends Phobject {
+
+  private $number;
+
+  public function __construct($raw_number) {
+    $number = preg_replace('/[^\d]+/', '', $raw_number);
+
+    if (!preg_match('/^[1-9]\d{1,14}\z/', $number)) {
+      throw new Exception(
+        pht(
+          'Phone number ("%s") is not in a recognized format.',
+          $raw_number));
+    }
+
+    $this->number = $number;
+  }
+
+  public function toE164() {
+    return '+'.$this->number;
+  }
+
+}