diff --cc core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeCustomFormatter.php
index fe5fa75,31bd1d1..0000000
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeCustomFormatter.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeCustomFormatter.php
@@@ -42,8 -40,22 +42,8 @@@ class DateTimeCustomFormatter extends D
          /** @var \Drupal\Core\Datetime\DrupalDateTime $date */
          $date = $item->date;
  
-         $elements[$delta] = $this->buildDate($date);
 -        if ($this->getFieldSetting('datetime_type') == 'date') {
 -          // A date without time will pick up the current time, use the default.
 -          datetime_date_default_time($date);
 -        }
 -        $this->setTimeZone($date, $item->timezone);
 -
 -        $output = $this->formatDate($date);
++        $elements[$delta] = $this->buildDate($date, $item->timezone);
        }
 -      $elements[$delta] = [
 -        '#markup' => $output,
 -        '#cache' => [
 -          'contexts' => [
 -            'timezone',
 -          ],
 -        ],
 -      ];
      }
  
      return $elements;
diff --cc core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeDefaultFormatter.php
index 8f703fb,b330179..0000000
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeDefaultFormatter.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeDefaultFormatter.php
diff --cc core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimePlainFormatter.php
index 5bb6766,6b80133..0000000
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimePlainFormatter.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimePlainFormatter.php
@@@ -29,8 -30,22 +29,8 @@@ class DateTimePlainFormatter extends Da
          /** @var \Drupal\Core\Datetime\DrupalDateTime $date */
          $date = $item->date;
  
-         $elements[$delta] = $this->buildDate($date);
 -        if ($this->getFieldSetting('datetime_type') == 'date') {
 -          // A date without time will pick up the current time, use the default.
 -          datetime_date_default_time($date);
 -        }
 -        $this->setTimeZone($date, $item->timezone);
 -
 -        $output = $this->formatDate($date);
++        $elements[$delta] = $this->buildDate($date, $item->timezone);
        }
 -      $elements[$delta] = [
 -        '#cache' => [
 -          'contexts' => [
 -            'timezone',
 -          ],
 -        ],
 -        '#markup' => $output,
 -      ];
      }
  
      return $elements;
diff --cc core/modules/datetime/tests/src/Kernel/DateTimeItemTest.php
index 424cbd9,e452e6c..0000000
--- a/core/modules/datetime/tests/src/Kernel/DateTimeItemTest.php
+++ b/core/modules/datetime/tests/src/Kernel/DateTimeItemTest.php
@@@ -46,11 -31,14 +46,14 @@@ class DateTimeItemTest extends FieldKer
        'field_name' => 'field_datetime',
        'type' => 'datetime',
        'entity_type' => 'entity_test',
-       'settings' => array('datetime_type' => DateTimeItem::DATETIME_TYPE_DATETIME),
+       'settings' => array(
 -        'datetime_type' => 'date',
++        'datetime_type' => DateTimeItem::DATETIME_TYPE_DATETIME,
+         'timezone_handling' => 'site',
+       ),
      ));
 -    $field_storage->save();
 -    $field = FieldConfig::create([
 -      'field_storage' => $field_storage,
 +    $this->fieldStorage->save();
 +    $this->field = FieldConfig::create([
 +      'field_storage' => $this->fieldStorage,
        'bundle' => 'entity_test',
        'settings' => array(
          'default_value' => 'blank',
diff --git a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php
index 996d071..3d8684c 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php
@@ -160,7 +160,7 @@ public function viewElements(FieldItemListInterface $items, $langcode) {
       if ($item->date) {
         /** @var \Drupal\Core\Datetime\DrupalDateTime $date */
         $date = $item->date;
-        $elements[$delta] = $this->buildDateWithIsoAttribute($date);
+        $elements[$delta] = $this->buildDateWithIsoAttribute($date, $item->timezone);
 
         if (!empty($item->_attributes)) {
           $elements[$delta]['#attributes'] += $item->_attributes;
@@ -231,16 +231,18 @@ protected function getFormatSettings() {
    *
    * @param \Drupal\Core\Datetime\DrupalDateTime $date
    *   A date object.
+   * @param string $timezone
+   *   (optional) A timezone to explicitly set the date to.
    *
    * @return array
    *   A render array.
    */
-  protected function buildDate(DrupalDateTime $date) {
+  protected function buildDate(DrupalDateTime $date, $timezone = NULL) {
     if ($this->getFieldSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE) {
       // A date without time will pick up the current time, use the default.
       datetime_date_default_time($date);
     }
-    $this->setTimeZone($date);
+    $this->setTimeZone($date, $timezone);
 
     $build = [
       '#markup' => $this->formatDate($date),
@@ -259,11 +261,13 @@ protected function buildDate(DrupalDateTime $date) {
    *
    * @param \Drupal\Core\Datetime\DrupalDateTime $date
    *   A date object.
+   * @param string $timezone
+   *   (optional) A timezone to explicitly set the date to.
    *
    * @return array
    *   A render array.
    */
-  protected function buildDateWithIsoAttribute(DrupalDateTime $date) {
+  protected function buildDateWithIsoAttribute(DrupalDateTime $date, $timezone = NULL) {
     if ($this->getFieldSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE) {
       // A date without time will pick up the current time, use the default.
       datetime_date_default_time($date);
@@ -272,7 +276,7 @@ protected function buildDateWithIsoAttribute(DrupalDateTime $date) {
     // Create the ISO date in Universal Time.
     $iso_date = $date->format("Y-m-d\TH:i:s") . 'Z';
 
-    $this->setTimeZone($date);
+    $this->setTimeZone($date, $timezone);
 
     $build = [
       '#theme' => 'time',