diff --git a/core/modules/user/lib/Drupal/user/UserStorage.php b/core/modules/user/lib/Drupal/user/UserStorage.php
index c2574b6..544971f 100644
--- a/core/modules/user/lib/Drupal/user/UserStorage.php
+++ b/core/modules/user/lib/Drupal/user/UserStorage.php
@@ -162,7 +162,6 @@ public function getSchema() {
     // performant.
     $schema['users']['fields']['access']['not null'] = TRUE;
     $schema['users']['fields']['created']['not null'] = TRUE;
-    $schema['users']['fields']['mail']['not null'] = TRUE;
     $schema['users']['fields']['name']['not null'] = TRUE;
 
     // The "users" table does not use serial identifiers.