diff -u b/core/modules/file/file.js b/core/modules/file/file.js
--- b/core/modules/file/file.js
+++ b/core/modules/file/file.js
@@ -36,10 +36,6 @@
         elements = settings.file.elements;
         Object.keys(elements).forEach(initFileValidation);
       }
-
-      // Trigger visible state to allow States to react to the loading of
-      // this element.
-      $(document).trigger('state:visible');
     },
     detach: function (context, settings, trigger) {
       var $context = $(context);
@@ -140 +136 @@
-})(jQuery, Drupal);
\ No newline at end of file
+})(jQuery, Drupal);
diff -u b/core/modules/file/src/Element/ManagedFile.php b/core/modules/file/src/Element/ManagedFile.php
--- b/core/modules/file/src/Element/ManagedFile.php
+++ b/core/modules/file/src/Element/ManagedFile.php
@@ -355,15 +355,16 @@
 
     // Add states to ajax wrapper so states.js can potentially attach this
     // element as a Dependent.
-    $attributes = '';
+    $attributes = new Attribute(['id' => $ajax_wrapper_id]);
     if (isset($element['#states']) && !empty($element['#states'])) {
-      $attributes = new Attribute([
-        'data-drupal-states' => json_encode($element['#states']),
-      ]);
+      $attributes->offsetSet('data-drupal-states', json_encode($element['#states']));
+
+      // Add states to the file form element itself.
+      $element['upload']['#states'] = $element['#states'];
     }
 
     // Prefix and suffix used for Ajax replacement.
-    $element['#prefix'] = '<div id="' . $ajax_wrapper_id . '"' . $attributes . '>';
+    $element['#prefix'] = '<div' . $attributes . '>';
     $element['#suffix'] = '</div>';
 
     return $element;
diff -u b/core/modules/file/tests/modules/file_test_states/src/Form/FileTestStatesForm.php b/core/modules/file/tests/modules/file_test_states/src/Form/FileTestStatesForm.php
--- b/core/modules/file/tests/modules/file_test_states/src/Form/FileTestStatesForm.php
+++ b/core/modules/file/tests/modules/file_test_states/src/Form/FileTestStatesForm.php
@@ -39,6 +39,13 @@
         'visible'  => [':input[name="toggle"]' => ['checked' => TRUE]],
       ],
     ];
+    $form['managed_file_initially_optional'] = [
+      '#type' => 'managed_file',
+      '#title' => t('Managed File Initially Optional'),
+      '#states' => [
+        'required'  => [':input[name="toggle"]' => ['checked' => TRUE]],
+      ],
+    ];
     return $form;
   }
 
diff -u b/core/modules/file/tests/src/FunctionalJavascript/FileManagedStateTest.php b/core/modules/file/tests/src/FunctionalJavascript/FileManagedStateTest.php
--- b/core/modules/file/tests/src/FunctionalJavascript/FileManagedStateTest.php
+++ b/core/modules/file/tests/src/FunctionalJavascript/FileManagedStateTest.php
@@ -19,13 +19,6 @@
   public static $modules = ['file_test_states', 'file'];
 
   /**
-   * {@inheritdoc}
-   */
-  protected function setUp() {
-    parent::setUp();
-  }
-
-  /**
    * Tests if managed file is correctly hidden with states.
    */
   public function testFileStateVisible() {
@@ -40,6 +33,7 @@
     // Now get the fields from the page.
     $field_initially_visible = $page->findField('files[managed_file_initially_visible]');
     $field_initially_hidden = $page->findField('files[managed_file_initially_hidden]');
+    $field_initially_optional = $page->findField('files[managed_file_initially_optional]');
 
     // Check that the initially visible managed file is visible.
     $this->assertTrue($field_initially_visible->isVisible());
@@ -47,6 +41,9 @@
     // Check that the initially hidden managed file is hidden.
     $this->assertFalse($field_initially_hidden->isVisible());
 
+    // Check that the initially optional managed file is optional.
+    $this->assertFalse($field_initially_optional->hasAttribute('required'));
+
     // Toggle the fields.
     $page->findField('toggle')->click();
 
@@ -55,6 +52,9 @@
 
     // Check that the initially hidden managed file is now visible.
     $this->assertTrue($field_initially_hidden->isVisible());
+
+    // Check that the initially optional managed file is now required.
+    $this->assertTrue($field_initially_optional->hasAttribute('required'));
   }
 
 }