diff --git a/core/lib/Drupal/Core/Datetime/DateHelper.php b/core/lib/Drupal/Core/Datetime/DateHelper.php
index 168ef62740..a5feebf1d2 100644
--- a/core/lib/Drupal/Core/Datetime/DateHelper.php
+++ b/core/lib/Drupal/Core/Datetime/DateHelper.php
@@ -291,10 +291,10 @@ public static function weekDaysOrdered($weekdays) {
   public static function years($min = 0, $max = 0, $required = FALSE) {
     // Ensure $min and $max are valid values.
     if (empty($min)) {
-      $min = intval(date('Y', REQUEST_TIME) - 3);
+      $min = intval(date('Y', \Drupal::time()->getRequestTime()) - 3);
     }
     if (empty($max)) {
-      $max = intval(date('Y', REQUEST_TIME) + 3);
+      $max = intval(date('Y', \Drupal::time()->getRequestTime()) + 3);
     }
     $none = ['' => ''];
     $range = range($min, $max);
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampFormatter.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampFormatter.php
index cbc6d7ddd5..55463da624 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampFormatter.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampFormatter.php
@@ -106,7 +106,7 @@ public function settingsForm(array $form, FormStateInterface $form_state) {
     $date_formats = [];
 
     foreach ($this->dateFormatStorage->loadMultiple() as $machine_name => $value) {
-      $date_formats[$machine_name] = $this->t('@name format: @date', ['@name' => $value->label(), '@date' => $this->dateFormatter->format(REQUEST_TIME, $machine_name)]);
+      $date_formats[$machine_name] = $this->t('@name format: @date', ['@name' => $value->label(), '@date' => $this->dateFormatter->format(\Drupal::time()->getRequestTime(), $machine_name)]);
     }
 
     $date_formats['custom'] = $this->t('Custom');
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/ChangedItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/ChangedItem.php
index bd2e129f29..9e737758ab 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/ChangedItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/ChangedItem.php
@@ -30,7 +30,7 @@ public function preSave() {
 
     // Set the timestamp to request time if it is not set.
     if (!$this->value) {
-      $this->value = REQUEST_TIME;
+      $this->value = \Drupal::time()->getRequestTime();
     }
     else {
       // On an existing entity translation, the changed timestamp will only be
@@ -47,7 +47,7 @@ public function preSave() {
       if (!$entity->isNew() && $original && $original->hasTranslation($langcode)) {
         $original_value = $original->getTranslation($langcode)->get($this->getFieldDefinition()->getName())->value;
         if ($this->value == $original_value && $entity->hasTranslationChanges()) {
-          $this->value = REQUEST_TIME;
+          $this->value = \Drupal::time()->getRequestTime();
         }
       }
     }
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/CreatedItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/CreatedItem.php
index da2e2a7450..78a66a7f84 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/CreatedItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/CreatedItem.php
@@ -22,7 +22,7 @@ class CreatedItem extends TimestampItem {
   public function applyDefaultValue($notify = TRUE) {
     parent::applyDefaultValue($notify);
     // Created fields default to the current timestamp.
-    $this->setValue(['value' => REQUEST_TIME], $notify);
+    $this->setValue(['value' => \Drupal::time()->getRequestTime()], $notify);
     return $this;
   }
 
diff --git a/core/lib/Drupal/Core/KeyValueStore/DatabaseStorageExpirable.php b/core/lib/Drupal/Core/KeyValueStore/DatabaseStorageExpirable.php
index 86d3dabc53..8eba51ffea 100644
--- a/core/lib/Drupal/Core/KeyValueStore/DatabaseStorageExpirable.php
+++ b/core/lib/Drupal/Core/KeyValueStore/DatabaseStorageExpirable.php
@@ -36,7 +36,7 @@ public function has($key) {
     return (bool) $this->connection->query('SELECT 1 FROM {' . $this->connection->escapeTable($this->table) . '} WHERE collection = :collection AND name = :key AND expire > :now', [
       ':collection' => $this->collection,
       ':key' => $key,
-      ':now' => REQUEST_TIME,
+      ':now' => \Drupal::time()->getRequestTime(),
     ])->fetchField();
   }
 
@@ -47,7 +47,7 @@ public function getMultiple(array $keys) {
     $values = $this->connection->query(
       'SELECT name, value FROM {' . $this->connection->escapeTable($this->table) . '} WHERE expire > :now AND name IN ( :keys[] ) AND collection = :collection',
       [
-        ':now' => REQUEST_TIME,
+        ':now' => \Drupal::time()->getRequestTime(),
         ':keys[]' => $keys,
         ':collection' => $this->collection,
       ])->fetchAllKeyed();
@@ -62,7 +62,7 @@ public function getAll() {
       'SELECT name, value FROM {' . $this->connection->escapeTable($this->table) . '} WHERE collection = :collection AND expire > :now',
       [
         ':collection' => $this->collection,
-        ':now' => REQUEST_TIME,
+        ':now' => \Drupal::time()->getRequestTime(),
       ])->fetchAllKeyed();
     return array_map([$this->serializer, 'decode'], $values);
   }
@@ -78,7 +78,7 @@ public function setWithExpire($key, $value, $expire) {
       ])
       ->fields([
         'value' => $this->serializer->encode($value),
-        'expire' => REQUEST_TIME + $expire,
+        'expire' => \Drupal::time()->getRequestTime() + $expire,
       ])
       ->execute();
   }
diff --git a/core/lib/Drupal/Core/Queue/DatabaseQueue.php b/core/lib/Drupal/Core/Queue/DatabaseQueue.php
index 1d0621e0e5..471316ba49 100644
--- a/core/lib/Drupal/Core/Queue/DatabaseQueue.php
+++ b/core/lib/Drupal/Core/Queue/DatabaseQueue.php
@@ -87,8 +87,9 @@ protected function doCreateItem($data) {
       ->fields([
         'name' => $this->name,
         'data' => serialize($data),
-        // We cannot rely on REQUEST_TIME because many items might be created
-        // by a single request which takes longer than 1 second.
+        // We cannot rely on \Drupal::time()->getRequestTime()
+        // because many items might be created by a single request which takes
+        // longer than 1 second.
         'created' => time(),
       ]);
     // Return the new serial ID, or FALSE on failure.
@@ -214,7 +215,7 @@ public function garbageCollection() {
     try {
       // Clean up the queue for failed batches.
       $this->connection->delete(static::TABLE_NAME)
-        ->condition('created', REQUEST_TIME - 864000, '<')
+        ->condition('created', \Drupal::time()->getRequestTime() - 864000, '<')
         ->condition('name', 'drupal_batch:%', 'LIKE')
         ->execute();
 
@@ -225,7 +226,7 @@ public function garbageCollection() {
           'expire' => 0,
         ])
         ->condition('expire', 0, '<>')
-        ->condition('expire', REQUEST_TIME, '<')
+        ->condition('expire', \Drupal::time()->getRequestTime(), '<')
         ->execute();
     }
     catch (\Exception $e) {
diff --git a/core/lib/Drupal/Core/Template/TwigPhpStorageCache.php b/core/lib/Drupal/Core/Template/TwigPhpStorageCache.php
index 995ce97803..d50075e234 100644
--- a/core/lib/Drupal/Core/Template/TwigPhpStorageCache.php
+++ b/core/lib/Drupal/Core/Template/TwigPhpStorageCache.php
@@ -111,7 +111,7 @@ public function write($key, $content) {
     $this->storage()->save($key, $content);
     // Save the last mtime.
     $cid = 'twig:' . $key;
-    $this->cache->set($cid, REQUEST_TIME);
+    $this->cache->set($cid, \Drupal::time()->getRequestTime());
   }
 
   /**
diff --git a/core/modules/aggregator/src/Entity/Feed.php b/core/modules/aggregator/src/Entity/Feed.php
index 4c3a5b856e..3e8dd3bea8 100644
--- a/core/modules/aggregator/src/Entity/Feed.php
+++ b/core/modules/aggregator/src/Entity/Feed.php
@@ -85,7 +85,7 @@ public function refreshItems() {
     $success = \Drupal::service('aggregator.items.importer')->refresh($this);
 
     // Regardless of successful or not, indicate that it has been checked.
-    $this->setLastCheckedTime(REQUEST_TIME);
+    $this->setLastCheckedTime(\Drupal::time()->getRequestTime());
     $this->setQueuedTime(0);
     $this->save();
 
diff --git a/core/modules/config_translation/src/FormElement/DateFormat.php b/core/modules/config_translation/src/FormElement/DateFormat.php
index d0ae033a42..8cd218e0ec 100644
--- a/core/modules/config_translation/src/FormElement/DateFormat.php
+++ b/core/modules/config_translation/src/FormElement/DateFormat.php
@@ -16,7 +16,7 @@ public function getTranslationElement(LanguageInterface $translation_language, $
     /** @var \Drupal\Core\Datetime\DateFormatterInterface $date_formatter */
     $date_formatter = \Drupal::service('date.formatter');
     $description = $this->t('A user-defined date format. See the <a href="http://php.net/manual/function.date.php">PHP manual</a> for available options.');
-    $format = $this->t('Displayed as %date_format', ['%date_format' => $date_formatter->format(REQUEST_TIME, 'custom', $translation_config)]);
+    $format = $this->t('Displayed as %date_format', ['%date_format' => $date_formatter->format(\Drupal::time()->getRequestTime(), 'custom', $translation_config)]);
 
     return [
       '#type' => 'textfield',
diff --git a/core/modules/datetime/src/Plugin/Field/FieldType/DateTimeItem.php b/core/modules/datetime/src/Plugin/Field/FieldType/DateTimeItem.php
index 3264069008..2c3ac8e90d 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldType/DateTimeItem.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldType/DateTimeItem.php
@@ -107,7 +107,7 @@ public static function generateSampleValue(FieldDefinitionInterface $field_defin
 
     // Just pick a date in the past year. No guidance is provided by this Field
     // type.
-    $timestamp = REQUEST_TIME - mt_rand(0, 86400 * 365);
+    $timestamp = \Drupal::time()->getRequestTime() - mt_rand(0, 86400 * 365);
     if ($type == DateTimeItem::DATETIME_TYPE_DATE) {
       $values['value'] = gmdate(static::DATE_STORAGE_FORMAT, $timestamp);
     }
diff --git a/core/modules/datetime_range/src/Plugin/Field/FieldType/DateRangeItem.php b/core/modules/datetime_range/src/Plugin/Field/FieldType/DateRangeItem.php
index 7c34ed127c..3a7d742525 100644
--- a/core/modules/datetime_range/src/Plugin/Field/FieldType/DateRangeItem.php
+++ b/core/modules/datetime_range/src/Plugin/Field/FieldType/DateRangeItem.php
@@ -94,7 +94,7 @@ public static function generateSampleValue(FieldDefinitionInterface $field_defin
 
     // Just pick a date in the past year. No guidance is provided by this Field
     // type.
-    $start = REQUEST_TIME - mt_rand(0, 86400 * 365) - 86400;
+    $start = \Drupal::time()->getRequestTime() - mt_rand(0, 86400 * 365) - 86400;
     $end = $start + 86400;
     if ($type == static::DATETIME_TYPE_DATETIME) {
       $values['value'] = gmdate(DateTimeItemInterface::DATETIME_STORAGE_FORMAT, $start);
diff --git a/core/modules/migrate_drupal_ui/src/Batch/MigrateUpgradeImportBatch.php b/core/modules/migrate_drupal_ui/src/Batch/MigrateUpgradeImportBatch.php
index c9c19a5c30..d66c4cb71e 100644
--- a/core/modules/migrate_drupal_ui/src/Batch/MigrateUpgradeImportBatch.php
+++ b/core/modules/migrate_drupal_ui/src/Batch/MigrateUpgradeImportBatch.php
@@ -286,7 +286,7 @@ public static function finished($success, $results, $operations, $elapsed) {
    */
   public static function onPostRowSave(MigratePostRowSaveEvent $event) {
     // We want to interrupt this batch and start a fresh one.
-    if ((time() - REQUEST_TIME) > static::$maxExecTime) {
+    if ((time() - \Drupal::time()->getRequestTime()) > static::$maxExecTime) {
       $event->getMigration()->interruptMigration(MigrationInterface::RESULT_INCOMPLETE);
     }
   }
@@ -317,7 +317,7 @@ public static function onPostImport(MigrateImportEvent $event) {
    */
   public static function onPostRowDelete(MigrateRowDeleteEvent $event) {
     // We want to interrupt this batch and start a fresh one.
-    if ((time() - REQUEST_TIME) > static::$maxExecTime) {
+    if ((time() - \Drupal::time()->getRequestTime()) > static::$maxExecTime) {
       $event->getMigration()->interruptMigration(MigrationInterface::RESULT_INCOMPLETE);
     }
   }
diff --git a/core/modules/views/src/ViewExecutable.php b/core/modules/views/src/ViewExecutable.php
index 9ee37041c0..716067623e 100644
--- a/core/modules/views/src/ViewExecutable.php
+++ b/core/modules/views/src/ViewExecutable.php
@@ -1686,7 +1686,7 @@ public function preExecute($args = []) {
     \Drupal::moduleHandler()->invokeAll('views_pre_view', [$this, $display_id, &$this->args]);
 
     // Allow hook_views_pre_view() to set the dom_id, then ensure it is set.
-    $this->dom_id = !empty($this->dom_id) ? $this->dom_id : hash('sha256', $this->storage->id() . REQUEST_TIME . mt_rand());
+    $this->dom_id = !empty($this->dom_id) ? $this->dom_id : hash('sha256', $this->storage->id() . \Drupal::time()->getRequestTime() . mt_rand());
 
     // Allow the display handler to set up for execution
     $this->display_handler->preExecute();