diff --git a/core/lib/Drupal/Core/Mail/Plugin/Mail/PhpMail.php b/core/lib/Drupal/Core/Mail/Plugin/Mail/PhpMail.php
index caa2af3..1a97b66 100644
--- a/core/lib/Drupal/Core/Mail/Plugin/Mail/PhpMail.php
+++ b/core/lib/Drupal/Core/Mail/Plugin/Mail/PhpMail.php
@@ -8,6 +8,7 @@
 namespace Drupal\Core\Mail\Plugin\Mail;
 
 use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Mail\MailFormatHelper;
 use Drupal\Core\Mail\MailInterface;
 use Drupal\Core\Site\Settings;
 
@@ -35,7 +36,7 @@ public function format(array $message) {
     // Join the body array into one string.
     $message['body'] = implode("\n\n", $message['body']);
     // Convert any HTML to plain-text.
-    $message['body'] = drupal_html_to_text($message['body']);
+    $message['body'] = MailFormatHelper::htmlToText($message['body']);
     // Wrap the mail body for sending.
     $message['body'] = drupal_wrap_mail($message['body']);
 
diff --git a/core/modules/contact/src/MessageViewBuilder.php b/core/modules/contact/src/MessageViewBuilder.php
index 23e9b43..4717338 100644
--- a/core/modules/contact/src/MessageViewBuilder.php
+++ b/core/modules/contact/src/MessageViewBuilder.php
@@ -10,6 +10,7 @@
 use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\EntityViewBuilder;
 use Drupal\Component\Utility\String;
+use Drupal\Core\Mail\MailFormatHelper;
 use Drupal\Core\Render\Element;
 
 /**
@@ -55,7 +56,8 @@ public function view(EntityInterface $entity, $view_mode = 'full', $langcode = N
 
     if ($view_mode == 'mail') {
       // Convert field labels into headings.
-      // @todo Improve drupal_html_to_text() to convert DIVs correctly.
+      // @todo Improve \Drupal\Core\Mail\MailFormatHelper::htmlToText() to
+      // convert DIVs correctly.
       foreach (Element::children($build) as $key) {
         if (isset($build[$key]['#label_display']) && $build[$key]['#label_display'] == 'above') {
           $build[$key] += array('#prefix' => '');
@@ -64,7 +66,7 @@ public function view(EntityInterface $entity, $view_mode = 'full', $langcode = N
         }
       }
       $build = array(
-        '#markup' => drupal_html_to_text(drupal_render($build)),
+        '#markup' => MailFormatHelper::htmlToText(drupal_render($build)),
       );
     }
     return $build;
diff --git a/core/modules/contact/src/Tests/ContactSitewideTest.php b/core/modules/contact/src/Tests/ContactSitewideTest.php
index beee430..5fcf023 100644
--- a/core/modules/contact/src/Tests/ContactSitewideTest.php
+++ b/core/modules/contact/src/Tests/ContactSitewideTest.php
@@ -8,6 +8,7 @@
 namespace Drupal\contact\Tests;
 
 use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Mail\MailFormatHelper;
 use Drupal\simpletest\WebTestBase;
 use Drupal\Core\Entity\EntityTypeInterface;
 
@@ -299,7 +300,7 @@ function testAutoReply() {
     // We are testing the auto-reply, so there should be one email going to the sender.
     $captured_emails = $this->drupalGetMails(array('id' => 'contact_page_autoreply', 'to' => $email));
     $this->assertEqual(count($captured_emails), 1);
-    $this->assertEqual(trim($captured_emails[0]['body']), trim(drupal_html_to_text($foo_autoreply)));
+    $this->assertEqual(trim($captured_emails[0]['body']), trim(MailFormatHelper::htmlToText($foo_autoreply)));
 
     // Test the auto-reply for form 'bar'.
     $email = $this->randomMachineName(32) . '@example.com';
@@ -308,7 +309,7 @@ function testAutoReply() {
     // Auto-reply for form 'bar' should result in one auto-reply email to the sender.
     $captured_emails = $this->drupalGetMails(array('id' => 'contact_page_autoreply', 'to' => $email));
     $this->assertEqual(count($captured_emails), 1);
-    $this->assertEqual(trim($captured_emails[0]['body']), trim(drupal_html_to_text($bar_autoreply)));
+    $this->assertEqual(trim($captured_emails[0]['body']), trim(MailFormatHelper::htmlToText($bar_autoreply)));
 
     // Verify that no auto-reply is sent when the auto-reply field is left blank.
     $email = $this->randomMachineName(32) . '@example.com';
diff --git a/core/modules/system/src/Tests/Mail/HtmlToTextTest.php b/core/modules/system/src/Tests/Mail/HtmlToTextTest.php
index 0b8315c..7f6e4b3 100644
--- a/core/modules/system/src/Tests/Mail/HtmlToTextTest.php
+++ b/core/modules/system/src/Tests/Mail/HtmlToTextTest.php
@@ -9,11 +9,12 @@
 
 use Drupal\Component\Utility\String;
 use Drupal\Component\Utility\Unicode;
+use Drupal\Core\Mail\MailFormatHelper;
 use Drupal\Core\Site\Settings;
 use Drupal\simpletest\WebTestBase;
 
 /**
- * Tests for drupal_html_to_text().
+ * Tests for \Drupal\Core\Mail\MailFormatHelper::htmlToText().
  *
  * @group Mail
  */
@@ -38,7 +39,8 @@ protected function stringToHtml($text) {
   }
 
   /**
-   * Helper function for testing drupal_html_to_text().
+   * Helper function for testing
+   * \Drupal\Core\Mail\MailFormatHelper::htmlToText().
    *
    * @param $html
    *   The source HTML string to be converted.
@@ -48,13 +50,14 @@ protected function stringToHtml($text) {
    *   A text message to display in the assertion message.
    * @param $allowed_tags
    *   (optional) An array of allowed tags, or NULL to default to the full
-   *   set of tags supported by drupal_html_to_text().
+   *   set of tags supported by
+   *   \Drupal\Core\Mail\MailFormatHelper::htmlToText().
    */
   protected function assertHtmlToText($html, $text, $message, $allowed_tags = NULL) {
     preg_match_all('/<([a-z0-6]+)/', drupal_strtolower($html), $matches);
     $tested_tags = implode(', ', array_unique($matches[1]));
     $message .= ' (' . $tested_tags . ')';
-    $result = drupal_html_to_text($html, $allowed_tags);
+    $result = MailFormatHelper::htmlToText($html, $allowed_tags);
     $pass = $this->assertEqual($result, $text, String::checkPlain($message));
     $verbose = 'html = <pre>' . $this->stringToHtml($html)
       . '</pre><br />' . 'result = <pre>' . $this->stringToHtml($result)
@@ -67,7 +70,8 @@ protected function assertHtmlToText($html, $text, $message, $allowed_tags = NULL
   }
 
   /**
-   * Test all supported tags of drupal_html_to_text().
+   * Test all supported tags of
+   * \Drupal\Core\Mail\MailFormatHelper::htmlToText().
    */
   public function testTags() {
     global $base_path, $base_url;
@@ -162,10 +166,12 @@ public function testTags() {
   }
 
   /**
-   * Test $allowed_tags argument of drupal_html_to_text().
+   * Test $allowed_tags argument of
+   * \Drupal\Core\Mail\MailFormatHelper::htmlToText().
    */
   public function testDrupalHtmlToTextArgs() {
-    // The second parameter of drupal_html_to_text() overrules the allowed tags.
+    // The second parameter of \Drupal\Core\Mail\MailFormatHelper::htmlToText()
+    // overrules the allowed tags.
     $this->assertHtmlToText(
       'Drupal <b>Drupal</b> Drupal',
       "Drupal *Drupal* Drupal\n",
@@ -235,7 +241,7 @@ public function testDrupalHtmlToTextBlockTagToNewline() {
       . '<ul><li>[ul-li]</li>'
       . '<li>[li-ul]</li></ul>'
       . '[text]';
-    $output = drupal_html_to_text($input);
+    $output = MailFormatHelper::htmlToText($input);
     $pass = $this->assertFalse(
       preg_match('/\][^\n]*\[/s', $output),
       'Block-level HTML tags should force newlines'
@@ -245,7 +251,7 @@ public function testDrupalHtmlToTextBlockTagToNewline() {
     }
     $output_upper = Unicode::strtoupper($output);
     $upper_input = Unicode::strtoupper($input);
-    $upper_output = drupal_html_to_text($upper_input);
+    $upper_output = MailFormatHelper::htmlToText($upper_input);
     $pass = $this->assertEqual(
       $upper_output,
       $output_upper,
@@ -331,7 +337,8 @@ public function testDrupalHtmlToTextParagraphs() {
   }
 
   /**
-   * Tests that drupal_html_to_text() wraps before 1000 characters.
+   * Tests that \Drupal\Core\Mail\MailFormatHelper::htmlToText() wraps before
+   * 1000 characters.
    *
    * RFC 3676 says, "The Text/Plain media type is the lowest common
    * denominator of Internet email, with lines of no more than 998 characters."
@@ -344,7 +351,7 @@ public function testDrupalHtmlToTextParagraphs() {
    */
   public function testVeryLongLineWrap() {
     $input = 'Drupal<br /><p>' . str_repeat('x', 2100) . '</><br />Drupal';
-    $output = drupal_html_to_text($input);
+    $output = MailFormatHelper::htmlToText($input);
     $eol = Settings::get('mail_line_endings', PHP_EOL);
 
     $maximum_line_length = 0;
diff --git a/core/modules/system/system.api.php b/core/modules/system/system.api.php
index e306b09..4e98a64 100644
--- a/core/modules/system/system.api.php
+++ b/core/modules/system/system.api.php
@@ -6,6 +6,7 @@
  */
 
 use Drupal\Component\Utility\String;
+use Drupal\Core\Mail\MailFormatHelper;
 use Drupal\Core\Url;
 
 /**
@@ -482,7 +483,7 @@ function hook_mail($key, &$message, $params) {
   $subject = strtr($context['subject'], $variables);
   $body = strtr($context['message'], $variables);
   $message['subject'] .= str_replace(array("\r", "\n"), '', $subject);
-  $message['body'][] = drupal_html_to_text($body);
+  $message['body'][] = MailFormatHelper::htmlToText($body);
 }
 
 /**