diff --git a/core/modules/file/file.field.inc b/core/modules/file/file.field.inc
index 67db185..c812f3f 100644
--- a/core/modules/file/file.field.inc
+++ b/core/modules/file/file.field.inc
@@ -12,39 +12,34 @@
 /**
  * Returns HTML for an individual file upload widget.
  *
- * @param $variables
- *   An associative array containing:
- *   - element: A render element representing the widget.
+ * Default template: file-widget.html.twig.
  *
- * @ingroup themeable
+ * @param array $variables
+ *   An associative array containing:
+ *   - element: A render element representing the file.
  */
-function theme_file_widget($variables) {
+function template_preprocess_file_widget(&$variables) {
   $element = $variables['element'];
-  $output = '';
-
-  // The "form-managed-file" class is required for proper Ajax functionality.
-  $output .= '<div class="file-widget form-managed-file clearfix">';
   if (!empty($element['fids']['#value'])) {
     // Add the file size after the file name.
     $file = reset($element['#files']);
     $element['file_' . $file->id()]['filename']['#suffix'] = ' <span class="file-size">(' . format_size($file->getSize()) . ')</span> ';
   }
-  $output .= drupal_render_children($element);
-  $output .= '</div>';
-
-  return $output;
+  $variables['element'] = $element;
+  // The "form-managed-file" class is required for proper Ajax functionality.
+  $variables['attributes'] = array('class' => array('file-widget', 'form-managed-file', 'clearfix'));
 }
 
 /**
- * Returns HTML for a group of file upload widgets.
+ * Prepares variables for multi file form widget templates.
+ *
+ * Default template: file-widget-multiple.html.twig.
  *
- * @param $variables
+ * @param array $variables
  *   An associative array containing:
  *   - element: A render element representing the widgets.
- *
- * @ingroup themeable
  */
-function theme_file_widget_multiple($variables) {
+function template_preprocess_file_widget_multiple(&$variables) {
   $element = $variables['element'];
 
   // Special ID and classes for draggable tables.
@@ -132,7 +127,7 @@ function theme_file_widget_multiple($variables) {
     );
   }
 
-  $build = array(
+  $variables['table'] = array(
     '#type' => 'table',
     '#header' => $headers,
     '#rows' => $rows,
@@ -148,25 +143,22 @@ function theme_file_widget_multiple($variables) {
     ),
   );
 
-  $output = empty($rows) ? '' : drupal_render($build);
-  $output .= drupal_render_children($element);
-  return $output;
+  $variables['element'] = $element;
 }
 
-
 /**
- * Returns HTML for help text based on file upload validators.
+ * Prepares variables for file upload help text templates.
  *
- * @param $variables
+ * Default template: file-upload-help.html.twig.
+ *
+ * @param array $variables
  *   An associative array containing:
  *   - description: The normal description for this field, specified by the
  *     user.
  *   - upload_validators: An array of upload validators as used in
  *     $element['#upload_validators'].
- *
- * @ingroup themeable
  */
-function theme_file_upload_help($variables) {
+function template_preprocess_file_upload_help(&$variables) {
   $description = $variables['description'];
   $upload_validators = $variables['upload_validators'];
   $cardinality = $variables['cardinality'];
@@ -208,7 +200,7 @@ function theme_file_upload_help($variables) {
     }
   }
 
-  return implode(' ', $descriptions);
+  $variables['descriptions'] = $descriptions;
 }
 
 /**
@@ -234,38 +226,3 @@ function file_field_find_file_reference_column(FieldDefinitionInterface $field)
   }
   return FALSE;
 }
-
-/**
- * Returns HTML for a file attachments table.
- *
- * @param $variables
- *   An associative array containing:
- *   - items: field values, as a FileFieldItemList object.
- *
- * @ingroup themeable
- */
-function theme_file_formatter_table($variables) {
-  $header = array(t('Attachment'), t('Size'));
-  $rows = array();
-  foreach ($variables['items'] as $delta => $item) {
-    if ($item->isDisplayed() && $item->entity) {
-      $rows[] = array(
-        array(
-          'data' => array(
-            '#theme' => 'file_link',
-            '#file' => $item->entity,
-          ),
-        ),
-        format_size($item->entity->getSize()),
-      );
-    }
-  }
-
-  $build = array(
-    '#type' => 'table',
-    '#header' => $header,
-    '#rows' => $rows,
-  );
-
-  return empty($rows) ? '' : drupal_render($build);
-}
diff --git a/core/modules/file/file.module b/core/modules/file/file.module
index 47b72ef..c5c9676 100644
--- a/core/modules/file/file.module
+++ b/core/modules/file/file.module
@@ -586,29 +586,31 @@ function file_get_content_headers(File $file) {
  */
 function file_theme() {
   return array(
-    // file.module.
+    // From file.module.
     'file_link' => array(
       'variables' => array('file' => NULL, 'icon_directory' => NULL, 'description' => NULL, 'attributes' => array()),
-    ),
-    'file_icon' => array(
-      'variables' => array('file' => NULL, 'icon_directory' => NULL),
+      'template' => 'file-link',
     ),
     'file_managed_file' => array(
       'render element' => 'element',
+      'template' => 'file-managed-file',
     ),
 
-    // file.field.inc.
+    // From file.field.inc.
     'file_widget' => array(
       'render element' => 'element',
+      'template' => 'file-widget',
+      'file' => 'file.field.inc',
     ),
     'file_widget_multiple' => array(
       'render element' => 'element',
-    ),
-    'file_formatter_table' => array(
-      'variables' => array('items' => NULL),
+      'template' => 'file-widget-multiple',
+      'file' => 'file.field.inc',
     ),
     'file_upload_help' => array(
       'variables' => array('description' => NULL, 'upload_validators' => NULL, 'cardinality' => NULL),
+      'template' => 'file-upload-help',
+      'file' => 'file.field.inc',
     ),
   );
 }
@@ -1537,32 +1539,25 @@ function file_managed_file_save_upload($element, array &$form_state) {
 }
 
 /**
- * Returns HTML for a managed file element.
+ * Prepares variables for file form widget templates.
+ *
+ * Default template: file-managed-file.html.twig.
  *
- * @param $variables
+ * @param array $variables
  *   An associative array containing:
  *   - element: A render element representing the file.
- *
- * @ingroup themeable
  */
-function theme_file_managed_file($variables) {
+function template_preprocess_file_managed_file(&$variables) {
   $element = $variables['element'];
 
-  $attributes = array();
+  $variables['attributes'] = array();
   if (isset($element['#id'])) {
-    $attributes['id'] = $element['#id'];
+    $variables['attributes']['id'] = $element['#id'];
   }
   if (!empty($element['#attributes']['class'])) {
-    $attributes['class'] = (array) $element['#attributes']['class'];
+    $variables['attributes']['class'] = (array) $element['#attributes']['class'];
   }
-  $attributes['class'][] = 'form-managed-file';
-
-  // This wrapper is required to apply JS behaviors and CSS styling.
-  $output = '';
-  $output .= '<div' . new Attribute($attributes) . '>';
-  $output .= drupal_render_children($element);
-  $output .= '</div>';
-  return $output;
+  $variables['attributes']['class'][] = 'form-managed-file';
 }
 
 /**
@@ -1601,24 +1596,34 @@ function file_managed_file_pre_render($element) {
 }
 
 /**
- * Returns HTML for a link to a file.
+ * Prepares variables for file link templates.
+ *
+ * Default template: file-link.html.twig.
  *
- * @param $variables
+ * @param array $variables
  *   An associative array containing:
  *   - file: A file object to which the link will be created.
  *   - icon_directory: (optional) A path to a directory of icons to be used for
- *     files. Defaults to the value of the "icon.directory"
- *     variable.
+ *     files. Defaults to the value of the "icon.directory" variable.
  *   - description: A description to be displayed instead of the filename.
  *   - attributes: An associative array of attributes to be placed in the a tag.
- *
- * @ingroup themeable
  */
-function theme_file_link($variables) {
+function template_preprocess_file_link(&$variables) {
   $file = $variables['file'];
   $options = array(
     'attributes' => $variables['attributes'],
   );
+  $icon_directory = $variables['icon_directory'];
+
+  $url = file_create_url($file->getFileUri());
+  $file_entity = ($file instanceof File) ? $file : file_load($file->fid);
+  $variables['icon'] = array(
+    '#theme' => 'image__file_icon',
+    '#uri' => file_icon_url($file_entity, $icon_directory),
+    '#alt' => '',
+    '#title' => check_plain($file_entity->getFilename()),
+    '#attributes' => array('class' => 'file-icon'),
+  );
 
   // Set options as per anchor format described at
   // http://microformats.org/wiki/file-format-examples
@@ -1626,41 +1631,15 @@ function theme_file_link($variables) {
 
   // Use the description as the link text if available.
   if (empty($variables['description'])) {
-    $link_text = $file->getFilename();
+    $link_text = $file_entity->getFilename();
   }
   else {
     $link_text = $variables['description'];
-    $options['attributes']['title'] = check_plain($file->getFilename());
+    $options['attributes']['title'] = check_plain($file_entity->getFilename());
   }
 
-  $file_icon = array(
-    '#theme' => 'file_icon',
-    '#file' => $file,
-    '#icon_directory' => $variables['icon_directory'],
-  );
-
-  return '<span class="file">' . drupal_render($file_icon) . ' ' . l($link_text, file_create_url($file->getFileUri()), $options) . '</span>';
-}
-
-/**
- * Returns HTML for an image with an appropriate icon for the given file.
- *
- * @param $variables
- *   An associative array containing:
- *   - file: A file entity for which to make an icon.
- *   - icon_directory: (optional) A path to a directory of icons to be used for
- *     files. Defaults to the value of the "icon.directory"
- *     variable.
- *
- * @ingroup themeable
- */
-function theme_file_icon($variables) {
-  $file = $variables['file'];
-  $icon_directory = $variables['icon_directory'];
-
-  $mime = check_plain($file->getMimeType());
-  $icon_url = file_icon_url($file, $icon_directory);
-  return '<img class="file-icon" alt="" title="' . $mime . '" src="' . $icon_url . '" />';
+  $variables['link'] = l($link_text, $url, $options);
+  $variables['attributes'] = array('class' => array('file'));
 }
 
 /**
diff --git a/core/modules/file/src/Plugin/Field/FieldFormatter/TableFormatter.php b/core/modules/file/src/Plugin/Field/FieldFormatter/TableFormatter.php
index 5f9d4bf..b5346c6 100644
--- a/core/modules/file/src/Plugin/Field/FieldFormatter/TableFormatter.php
+++ b/core/modules/file/src/Plugin/Field/FieldFormatter/TableFormatter.php
@@ -29,11 +29,31 @@ public function viewElements(FieldItemListInterface $items) {
     $elements = array();
 
     if (!$items->isEmpty()) {
-      // Display all values in a single element.
-      $elements[0] = array(
-        '#theme' => 'file_formatter_table',
-        '#items' => $items,
-      );
+
+      $header = array(t('Attachment'), t('Size'));
+      $rows = array();
+      foreach ($items as $delta => $item) {
+        if ($item->isDisplayed() && $item->entity) {
+          $rows[] = array(
+            array(
+              'data' => array(
+                '#theme' => 'file_link',
+                '#file' => $item->entity,
+              ),
+            ),
+            array('data' => format_size($item->entity->getSize())),
+          );
+        }
+      }
+
+      $elements[0] = array();
+      if (!empty($rows)) {
+        $elements[0] = array(
+          '#theme' => 'table__file_formatter_table',
+          '#header' => $header,
+          '#rows' => $rows,
+        );
+      }
     }
 
     return $elements;
diff --git a/core/modules/file/src/Plugin/views/field/FileMime.php b/core/modules/file/src/Plugin/views/field/FileMime.php
index ac98724..fd1c355 100644
--- a/core/modules/file/src/Plugin/views/field/FileMime.php
+++ b/core/modules/file/src/Plugin/views/field/FileMime.php
@@ -40,7 +40,7 @@ public function render(ResultRow $values) {
     $data = $values->{$this->field_alias};
     if (!empty($this->options['filemime_image']) && $data !== NULL && $data !== '') {
       $file_icon = array(
-        '#theme' => 'file_icon',
+        '#theme' => 'image__file_icon',
         '#file' => $values->_entity,
       );
       $data = drupal_render($file_icon);
diff --git a/core/modules/file/templates/file-link.html.twig b/core/modules/file/templates/file-link.html.twig
new file mode 100644
index 0000000..fbbf08b
--- /dev/null
+++ b/core/modules/file/templates/file-link.html.twig
@@ -0,0 +1,16 @@
+{#
+/**
+ * @file
+ * Default theme implementation for a link to a file.
+ *
+ * Available variables:
+ * - attributes: The HTML attributes for the containing element.
+ * - link: A link to the file.
+ * - icon: The icon image representing the file type.
+ *
+ * @see template_preprocess_file_link()
+ *
+ * @ingroup themeable
+ */
+#}
+<span{{ attributes }}>{{ icon }} {{ link }}</span>
diff --git a/core/modules/file/templates/file-managed-file.html.twig b/core/modules/file/templates/file-managed-file.html.twig
new file mode 100644
index 0000000..9a33ae1
--- /dev/null
+++ b/core/modules/file/templates/file-managed-file.html.twig
@@ -0,0 +1,17 @@
+{#
+/**
+ * @file
+ * Default theme implementation to display a file form widget.
+ *
+ * Available variables:
+ * - element: Form element for the file upload.
+ * - attributes: HTML attributes for the containing element.
+ *
+ * @see template_preprocess_file_managed_file()
+ *
+ * @ingroup themeable
+ */
+#}
+<div{{ attributes }}>
+  {{ element }}
+</div>
diff --git a/core/modules/file/templates/file-upload-help.html.twig b/core/modules/file/templates/file-upload-help.html.twig
new file mode 100644
index 0000000..fe4d194
--- /dev/null
+++ b/core/modules/file/templates/file-upload-help.html.twig
@@ -0,0 +1,14 @@
+{#
+/**
+ * @file
+ * Default theme implementation to display help text for file fields.
+ *
+ * Available variables:
+ * - descriptions: Lines of help text for uploading a file.
+ *
+ * @see template_preprocess_file_upload_help()
+ *
+ * @ingroup themeable
+ */
+#}
+{{ descriptions|join('<br />') }}
diff --git a/core/modules/file/templates/file-widget-multiple.html.twig b/core/modules/file/templates/file-widget-multiple.html.twig
new file mode 100644
index 0000000..25534a5
--- /dev/null
+++ b/core/modules/file/templates/file-widget-multiple.html.twig
@@ -0,0 +1,16 @@
+{#
+/**
+ * @file
+ * Default theme implementation to display a multi file form widget.
+ *
+ * Available variables:
+ * - table: Table of previously uploaded files.
+ * - element: The form element for uploading another file.
+ *
+ * @see template_preprocess_file_widget_multiple()
+ *
+ * @ingroup themeable
+ */
+#}
+{{ table }}
+{{ element }}
diff --git a/core/modules/file/templates/file-widget.html.twig b/core/modules/file/templates/file-widget.html.twig
new file mode 100644
index 0000000..892ed3d
--- /dev/null
+++ b/core/modules/file/templates/file-widget.html.twig
@@ -0,0 +1,17 @@
+{#
+/**
+ * @file
+ * Default theme implementation to display a file widget.
+ *
+ * Available variables:
+ * - element: Form element for the managed file.
+ * - attributes: Remaining HTML attributes for the containing element.
+ *
+ * @see template_preprocess_file_widget()
+ *
+ * @ingroup themeable
+ */
+#}
+<div{{ attributes }}>
+  {{ element }}
+</div>