diff --git a/framework/CHANGELOG.md b/framework/CHANGELOG.md
index 69c6cbb..64f1196 100644
--- a/framework/CHANGELOG.md
+++ b/framework/CHANGELOG.md
@@ -5,6 +5,7 @@ Yii Framework 2 Change Log
 -----------------------
 
 - Enh #11058: Add `$checkAjax` parameter to method `yii\web\Controller::redirect()` which controls redirection in AJAX and PJAX requests (ivanovyordan)
+- Enh #12385: Methods `addHeader()`, `setHeader()`, `getHeader()`, `setHeaders()` have been added to `yii\i18n\MessageInterface` allowing setup of custom message headers (klimov-paul)
 - Enh #12592: Optimized `yii\filters\AccessController` on processing accessrules (dynasource)
 - Enh #12938: Allow to pass additional parameters to `yii\base\View::renderDynamic()` (mikehaertl)
 - Enh #13006: Added a `/` to the `yii\captcha\Captcha::$captchaAction` string to work correctly in a module also (boehsermoe)
diff --git a/framework/UPGRADE.md b/framework/UPGRADE.md
index c81d206..01504ad 100644
--- a/framework/UPGRADE.md
+++ b/framework/UPGRADE.md
@@ -50,6 +50,14 @@ if you want to upgrade from version A to version C and there is
 version B between A and C, you need to follow the instructions
 for both A and B.
 
+Upgrade from Yii 2.0.x
+----------------------
+
+* Following new methods have been added to `yii\i18n\MessageInterface` `addHeader()`, `setHeader()`, `getHeader()`, `setHeaders()`
+  providing ability to setup custom mail headers. Make sure your provide implementation for those methods, while
+  creating your own mailer solution.
+
+
 Upgrade from Yii 2.0.11
 -----------------------
 
diff --git a/framework/mail/MessageInterface.php b/framework/mail/MessageInterface.php
index 3f1fae2..fd584cc 100644
--- a/framework/mail/MessageInterface.php
+++ b/framework/mail/MessageInterface.php
@@ -203,6 +203,41 @@ interface MessageInterface
     public function embedContent($content, array $options = []);
 
     /**
+     * Adds custom header value to the message.
+     * Several invocations of this method with the same name will add multiple header values.
+     * @param string $name header name.
+     * @param string $value header value.
+     * @return $this self reference.
+     * @since 2.1
+     */
+    public function addHeader($name, $value);
+
+    /**
+     * Sets custom header value to the message.
+     * @param string $name header name.
+     * @param string|array $value header value or values.
+     * @return $this self reference.
+     * @since 2.1
+     */
+    public function setHeader($name, $value);
+
+    /**
+     * Returns all values for the specified header.
+     * @param string $name header name.
+     * @return array header values list.
+     * @since 2.1
+     */
+    public function getHeader($name);
+
+    /**
+     * Sets custom header values to the message.
+     * @param array $headers headers in format: `[name => value]`.
+     * @return $this self reference.
+     * @since 2.1
+     */
+    public function setHeaders($headers);
+
+    /**
      * Sends this email message.
      * @param MailerInterface $mailer the mailer that should be used to send this message.
      * If null, the "mail" application component will be used instead.