diff --git a/core/lib/Drupal/Component/Transliteration/PHPTransliteration.php b/core/lib/Drupal/Component/Transliteration/PHPTransliteration.php
index 80982d2..88dd64c 100644
--- a/core/lib/Drupal/Component/Transliteration/PHPTransliteration.php
+++ b/core/lib/Drupal/Component/Transliteration/PHPTransliteration.php
@@ -76,19 +76,32 @@ public function __construct($data_directory = NULL) {
   }
 
   /**
-   * Implements TransliterationInterface::transliterate().
+   * {@inheritdoc}
    */
-  public function transliterate($string, $langcode = 'en', $unknown_character = '?') {
+  public function transliterate($string, $langcode = 'en', $unknown_character = '?', $max_length = NULL) {
     $result = '';
+    $length = 0;
     // Split into Unicode characters and transliterate each one.
     foreach (preg_split('//u', $string, 0, PREG_SPLIT_NO_EMPTY) as $character) {
       $code = self::ordUTF8($character);
+      $to_add = '';
       if ($code == -1) {
-        $result .= $unknown_character;
+        $to_add = $unknown_character;
       }
       else {
-        $result .= $this->replace($code, $langcode, $unknown_character);
+        $to_add = $this->replace($code, $langcode, $unknown_character);
       }
+
+      // Check if this exceeds the maximum allowed length.
+      if (isset($max_length)) {
+        $length += strlen($to_add);
+        if ($length > $max_length) {
+          // There is no more space.
+          return $result;
+        }
+      }
+
+      $result .= $to_add;
     }
 
     return $result;
diff --git a/core/lib/Drupal/Component/Transliteration/TransliterationInterface.php b/core/lib/Drupal/Component/Transliteration/TransliterationInterface.php
index b88a55d..8eda816 100644
--- a/core/lib/Drupal/Component/Transliteration/TransliterationInterface.php
+++ b/core/lib/Drupal/Component/Transliteration/TransliterationInterface.php
@@ -25,10 +25,14 @@
    * @param string $unknown_character
    *   (optional) The character to substitute for characters in $string without
    *   transliterated equivalents. Defaults to '?'.
+   * @param int $max_length
+   *   (optional) If provided, return at most this many characters, ensuring
+   *   that the transliteration does not split in the middle of an input
+   *   character's transliteration.
    *
    * @return string
    *   $string with non-US-ASCII characters transliterated to US-ASCII
    *   characters, and unknown characters replaced with $unknown_character.
    */
-  public function transliterate($string, $langcode = 'en', $unknown_character = '?');
+  public function transliterate($string, $langcode = 'en', $unknown_character = '?', $max_length = NULL);
 }
diff --git a/core/modules/system/lib/Drupal/system/Tests/Transliteration/TransliterationTest.php b/core/modules/system/lib/Drupal/system/Tests/Transliteration/TransliterationTest.php
index 7630b0b..2e5ed60 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Transliteration/TransliterationTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Transliteration/TransliterationTest.php
@@ -106,5 +106,13 @@ public function testPHPTransliteration() {
         '@actual' => $actual,
       )));
     }
+
+    // Test with max length, using German. It should never split up the
+    // transliteration of a single character.
+    $input = 'Ä Ö Ü Å Ø äöüåøhello';
+    $trunc_output = 'Ae Oe Ue A O aeoe';
+    $this->assertIdentical($trunc_output, $transliterator_service->transliterate($input, 'de', '?', 17), 'Truncating to 17 characters works');
+    $this->assertIdentical($trunc_output, $transliterator_service->transliterate($input, 'de', '?', 18), 'Truncating to 18 characters works');
+
   }
 }