diff --git a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeDefaultFormatter.php b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeDefaultFormatter.php
index 3fac252..03c92ae 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeDefaultFormatter.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeDefaultFormatter.php
@@ -86,7 +86,7 @@ public function viewElements(FieldItemListInterface $items, $langcode) {
    */
   protected function formatDate($date) {
     $format_type = $this->getSetting('format_type');
-    $timezone = $this->getSetting('timezone_override');
+    $timezone = $this->getSetting('timezone_override') ?: $date->getTimezone()->getName();
     return $this->dateFormatter->format($date->getTimestamp(), $format_type, '', $timezone != '' ? $timezone : NULL);
   }
 
diff --git a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php
index 5d5a40c..be9df38 100644
--- a/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php
+++ b/core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php
@@ -141,7 +141,7 @@ public function settingsSummary() {
    *   A DrupalDateTime object.
    */
   protected function setTimeZone(DrupalDateTime $date) {
-    if ($this->getFieldSetting('datetime_type') == DateTimeItem::DATETIME_TYPE_DATE) {
+    if ($this->getFieldSetting('datetime_type') === DateTimeItem::DATETIME_TYPE_DATE) {
       // A date without time has no timezone conversion.
       $timezone = DATETIME_STORAGE_TIMEZONE;
     }
diff --git a/core/modules/datetime/src/Tests/DateTimeFieldTest.php b/core/modules/datetime/src/Tests/DateTimeFieldTest.php
index d8787a3..4fde203 100644
--- a/core/modules/datetime/src/Tests/DateTimeFieldTest.php
+++ b/core/modules/datetime/src/Tests/DateTimeFieldTest.php
@@ -54,18 +54,25 @@ class DateTimeFieldTest extends WebTestBase {
   protected $field;
 
   /**
+   * An array of timezone extremes to test.
+   *
+   * @var string[]
+   */
+  protected static $timezones = [
+    // UTC-11.
+    'Pacific/Midway',
+    // UTC.
+    'UTC',
+    // UTC+14.
+    'Pacific/Auckland',
+  ];
+
+  /**
    * {@inheritdoc}
    */
   protected function setUp() {
     parent::setUp();
 
-    // Set an explicit site timezone, and disallow per-user timezones.
-    $this->config('system.date')
-      ->set('timezone.user.configurable', 0)
-      // A timezone with an offset greater than UTC+12 is used.
-      ->set('timezone.default', 'Pacific/Auckland')
-      ->save();
-
     $web_user = $this->drupalCreateUser(array(
       'access content',
       'view test entity',
@@ -118,6 +125,12 @@ protected function setUp() {
   function testDateField() {
     $field_name = $this->fieldStorage->getName();
 
+    // Loop through defined timezones to test that date-only fields work at the
+    // extremes.
+    foreach (static::$timezones as $timezone) {
+
+      $this->setSiteTimezone($timezone);
+
       // Display creation form.
       $this->drupalGet('entity_test/add');
       $this->assertFieldByName("{$field_name}[0][value][date]", '', 'Date element found.');
@@ -157,6 +170,12 @@ function testDateField() {
       $entity = EntityTest::load($id);
       $this->assertEqual('2012-12-31', $entity->{$field_name}->value);
 
+      // Reset display options since these get changed below.
+      $this->displayOptions = array(
+        'type' => 'datetime_default',
+        'label' => 'hidden',
+        'settings' => array('format_type' => 'medium') + $this->defaultSettings,
+      );
       // Verify that the date is output according to the formatter settings.
       $options = array(
         'format_type' => array('short', 'medium', 'long'),
@@ -172,9 +191,10 @@ function testDateField() {
           $this->renderTestEntity($id);
           switch ($setting) {
             case 'format_type':
-            // Verify that a date is displayed.
-            $expected = format_date($date->getTimestamp(), $new_value);
-            $expected_iso = format_date($date->getTimestamp(), 'custom', 'Y-m-d\TH:i:s\Z', 'UTC');
+              // Verify that a date is displayed. Since this is a date-only
+              // field, it is expected to display the time as 00:00:00.
+              $expected = format_date($date->getTimestamp(), $new_value, '', DATETIME_STORAGE_TIMEZONE);
+              $expected_iso = format_date($date->getTimestamp(), 'custom', 'Y-m-d\TH:i:s\Z', DATETIME_STORAGE_TIMEZONE);
               $this->renderTestEntity($id);
               $this->assertFieldByXPath('//time[@datetime="' . $expected_iso . '"]', $expected, SafeMarkup::format('Formatted date field using %value format displayed as %expected with %expected_iso attribute.', array('%value' => $new_value, '%expected' => $expected, '%expected_iso' => $expected_iso)));
               break;
@@ -250,6 +270,7 @@ function testDateField() {
       $this->renderTestEntity($id);
       $this->assertText($expected, SafeMarkup::format('Formatted date field using datetime_time_ago format displayed as %expected.', array('%expected' => $expected)));
     }
+  }
 
   /**
    * Tests date and time field.
@@ -884,4 +905,19 @@ protected function renderTestEntity($id, $view_mode = 'full', $reset = TRUE) {
     $this->verbose($output);
   }
 
+  /**
+   * Sets the site timezone to a given timezone.
+   *
+   * @param string $timezone
+   *   The timezone identifier to set.
+   */
+  protected function setSiteTimezone($timezone) {
+    // Set an explicit site timezone, and disallow per-user timezones.
+    $this->config('system.date')
+      ->set('timezone.user.configurable', 0)
+      // A timezone with an offset greater than UTC+12 is used.
+      ->set('timezone.default', $timezone)
+      ->save();
+  }
+
 }