diff --git a/lib/Config/Migrator.php b/lib/Config/Migrator.php
index 3775cc5b38..14bbbeb568 100644
--- a/lib/Config/Migrator.php
+++ b/lib/Config/Migrator.php
@@ -207,7 +207,7 @@ class Migrator {
       'unconfirmed_data longtext,',
       "source enum('form','imported','administrator','api','wordpress_user','woocommerce_user','woocommerce_checkout','unknown') DEFAULT 'unknown',",
       'count_confirmations int(11) unsigned NOT NULL DEFAULT 0,',
-      'unsubscribe_token varchar(15) NULL,',
+      'unsubscribe_token char(15) NULL,',
       'PRIMARY KEY  (id),',
       'UNIQUE KEY email (email),',
       'UNIQUE KEY unsubscribe_token (unsubscribe_token),',
@@ -276,7 +276,7 @@ class Migrator {
       'created_at timestamp NULL,', // must be NULL, see comment at the top
       'updated_at timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,',
       'deleted_at timestamp NULL,',
-      'unsubscribe_token varchar(15) NULL,',
+      'unsubscribe_token char(15) NULL,',
       'PRIMARY KEY  (id),',
       'UNIQUE KEY unsubscribe_token (unsubscribe_token),',
       'KEY type_status (type,status)',