diff --git a/core/modules/block/block.install b/core/modules/block/block.install
index 4363ef8..2c15a2a 100644
--- a/core/modules/block/block.install
+++ b/core/modules/block/block.install
@@ -206,13 +206,15 @@ function block_update_8007() {
     'info',
     'revision_id',
     'langcode',
-    'type'
+    'type',
+    'changed',
   ));
   $revision_insert = db_insert('custom_block_revision')->fields(array(
     'id',
     'revision_id',
     'log',
-    'info'
+    'info',
+    'changed',
   ));
   foreach ($results as $block) {
     $custom_block = array(
@@ -221,13 +223,15 @@ function block_update_8007() {
       'info' => $block->info,
       'revision_id' => $block->bid,
       'langcode' => Language::LANGCODE_NOT_SPECIFIED,
-      'type' => 'basic'
+      'type' => 'basic',
+      'changed' => REQUEST_TIME,
     );
     $revision = array(
       'id' => $block->bid,
       'revision_id' => $block->bid,
       'info' => $block->info,
-      'log' => 'Initial value from 7.x to 8.x upgrade'
+      'log' => 'Initial value from 7.x to 8.x upgrade',
+      'changed' => REQUEST_TIME,
     );
     $block_insert->values($custom_block);
     $revision_insert->values($revision);
diff --git a/core/modules/block/custom_block/custom_block.install b/core/modules/block/custom_block/custom_block.install
index 0e87811..3474559 100644
--- a/core/modules/block/custom_block/custom_block.install
+++ b/core/modules/block/custom_block/custom_block.install
@@ -48,6 +48,12 @@ function custom_block_schema() {
         'not null' => TRUE,
         'default' => '',
       ),
+      'changed' => array(
+        'description' => 'The Unix timestamp when the custom block was most recently saved.',
+        'type' => 'int',
+        'not null' => TRUE,
+        'default' => 0,
+      ),
       'langcode' => array(
         'description' => 'The {language}.langcode of this node.',
         'type' => 'varchar',
@@ -104,6 +110,12 @@ function custom_block_schema() {
         'default' => '',
         'description' => 'Block description.',
       ),
+      'changed' => array(
+        'description' => 'The Unix timestamp when the version was most recently saved.',
+        'type' => 'int',
+        'not null' => TRUE,
+        'default' => 0,
+      ),
     ),
     'primary key' => array('revision_id'),
   );
@@ -153,6 +165,12 @@ function custom_block_schema_0() {
         'not null' => TRUE,
         'default' => '',
       ),
+      'changed' => array(
+        'description' => 'The Unix timestamp when the custom block was most recently saved.',
+        'type' => 'int',
+        'not null' => TRUE,
+        'default' => 0,
+      ),
       'langcode' => array(
         'description' => 'The {language}.langcode of this node.',
         'type' => 'varchar',
@@ -209,6 +227,12 @@ function custom_block_schema_0() {
         'default' => '',
         'description' => 'Block description.',
       ),
+      'changed' => array(
+        'description' => 'The Unix timestamp when the version was most recently saved.',
+        'type' => 'int',
+        'not null' => TRUE,
+        'default' => 0,
+      ),
     ),
     'primary key' => array('revision_id'),
   );
diff --git a/core/modules/block/custom_block/lib/Drupal/custom_block/CustomBlockInterface.php b/core/modules/block/custom_block/lib/Drupal/custom_block/CustomBlockInterface.php
index 23e07e0..9343c15 100644
--- a/core/modules/block/custom_block/lib/Drupal/custom_block/CustomBlockInterface.php
+++ b/core/modules/block/custom_block/lib/Drupal/custom_block/CustomBlockInterface.php
@@ -8,11 +8,12 @@
 namespace Drupal\custom_block;

 use Drupal\Core\Entity\ContentEntityInterface;
+use Drupal\Core\Entity\EntityChangedInterface;

 /**
  * Provides an interface defining a custom block entity.
  */
-interface CustomBlockInterface extends ContentEntityInterface {
+interface CustomBlockInterface extends ContentEntityInterface, EntityChangedInterface {

   /**
    * Sets the theme value.
diff --git a/core/modules/block/custom_block/lib/Drupal/custom_block/Entity/CustomBlock.php b/core/modules/block/custom_block/lib/Drupal/custom_block/Entity/CustomBlock.php
index 698c39c..361bb21 100644
--- a/core/modules/block/custom_block/lib/Drupal/custom_block/Entity/CustomBlock.php
+++ b/core/modules/block/custom_block/lib/Drupal/custom_block/Entity/CustomBlock.php
@@ -190,6 +190,14 @@ public function uri() {
   /**
    * {@inheritdoc}
    */
+  public function preSave(EntityStorageControllerInterface $storage_controller) {
+    // Before saving the custom block, set changed time.
+    $this->changed->value = REQUEST_TIME;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function postSave(EntityStorageControllerInterface $storage_controller, $update = TRUE) {
     // Invalidate the block cache to update custom block-based derivatives.
     \Drupal::service('plugin.manager.block')->clearCachedDefinitions();
@@ -276,7 +284,19 @@ public static function baseFieldDefinitions($entity_type) {
       'description' => t('The revision log message.'),
       'type' => 'string_field',
     );
+    $properties['changed'] = array(
+      'label' => t('Changed'),
+      'description' => t('The time that the custom block was last edited.'),
+      'type' => 'integer_field',
+    );
     return $properties;
   }

+  /**
+   * {@inheritdoc}
+   */
+  public function getChangedTime() {
+    return $this->get('changed')->value;
+  }
+
 }
diff --git a/core/modules/block/custom_block/lib/Drupal/custom_block/Tests/CustomBlockSaveTest.php b/core/modules/block/custom_block/lib/Drupal/custom_block/Tests/CustomBlockSaveTest.php
index b74de5c..3efb47d 100644
--- a/core/modules/block/custom_block/lib/Drupal/custom_block/Tests/CustomBlockSaveTest.php
+++ b/core/modules/block/custom_block/lib/Drupal/custom_block/Tests/CustomBlockSaveTest.php
@@ -84,6 +84,8 @@ public function testDeterminingChanges() {
     $block->info->value = 'updated';
     $block->save();

+    $this->assertNotEqual($block->getChangedTime(), 0, 'Changed time maintained.');
+
     // The hook implementations custom_block_test_custom_block_presave() and
     // custom_block_test_custom_block_update() determine changes and change the
     // title.
diff --git a/core/modules/system/lib/Drupal/system/Tests/Upgrade/BlockUpgradePathTest.php b/core/modules/system/lib/Drupal/system/Tests/Upgrade/BlockUpgradePathTest.php
index bde6f60..fbba3ad 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Upgrade/BlockUpgradePathTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Upgrade/BlockUpgradePathTest.php
@@ -60,6 +60,32 @@ public function testBlockUpgradeTitleLength() {
     // Confirm that the custom block cannot be created with title longer than
     // the maximum number of characters.
     $this->assertText('Title cannot be longer than 255 characters');
+
+    $block = $this->createCustomBlock();
+    $this->assertNotEqual($block->getChangedTime(), 0, 'Changed time maintained.');
   }

+  /**
+   * Creates a custom block.
+   *
+   * @param string $title
+   *   (optional) Title of block. When no value is given uses a random name.
+   *   Defaults to FALSE.
+   * @param string $bundle
+   *   (optional) Bundle name. Defaults to 'basic'.
+   *
+   * @return Drupal\custom_block\Entity\CustomBlock
+   *   Created custom block.
+   */
+  protected function createCustomBlock($title = FALSE, $bundle = 'basic') {
+    $title = ($title ? : $this->randomName());
+    if ($custom_block = entity_create('custom_block', array(
+      'info' => $title,
+      'type' => $bundle,
+      'langcode' => 'en'
+    ))) {
+      $custom_block->save();
+    }
+    return $custom_block;
+  }
 }