diff -u b/core/modules/field/field.attach.inc b/core/modules/field/field.attach.inc
--- b/core/modules/field/field.attach.inc
+++ b/core/modules/field/field.attach.inc
@@ -115,8 +115,9 @@
 
     if (method_exists($target, $method)) {
       // Determine the list of languages to iterate on.
-      // @todo Unify language fallback handling between configurable and base
-      //   fields.
+      // @todo Unify the language fallback handling here between configurable
+      //   and base fields once field_available_languages() is either removed
+      //   or fixed to not require a configurable field: [#2067079].
       if ($field_definition instanceof FieldInstanceInterface) {
         $available_langcodes = field_available_languages($entity_type, $field_definition->getField());
         $langcodes = _field_language_suggestion($available_langcodes, $options['langcode'], $field_definition->getFieldName());
diff -u b/core/modules/field/field.module b/core/modules/field/field.module
--- b/core/modules/field/field.module
+++ b/core/modules/field/field.module
@@ -535,14 +535,7 @@
   }
 
   if ($formatter) {
-    // @todo Unify language fallback handling between configurable and base
-    //   fields.
-    if ($field_definition instanceof FieldInstanceInterface) {
-      $display_langcode = field_language($entity, $field_name, $langcode);
-    }
-    else {
-      $display_langcode = $entity->language()->id;
-    }
+    $display_langcode = field_language($entity, $field_name, $langcode);
 
     // Invoke the formatter's prepareView() and view() methods.
     $items = $entity->getTranslation($display_langcode)->get($field_name);