diff --git a/themable_forms.module b/themable_forms.module
index 5552642..b2d0877 100644
--- a/themable_forms.module
+++ b/themable_forms.module
@@ -14,7 +14,7 @@ use Drupal\Core\Render\Element;
 function themable_forms_theme_suggestions_form_element(array $variables) {
   $suggestions = ['form_element__type__' . $variables['element']['#type']];
   if (isset($variables['element']['#form_id'])) {
-    $suggestions[] = 'form_element__form-id__' . $variables['element']['#form_id'];
+    $suggestions[] = 'form_element__form_id__' . $variables['element']['#form_id'];
     $suggestions[] = 'form_element__' . $variables['element']['#form_id'] . '__' . $variables['element']['#type'];
   }