diff --git a/tools/postfix_transportlist.php b/tools/postfix_transportlist.php
new file mode 100644
index 0000000..967744f
--- /dev/null
+++ b/tools/postfix_transportlist.php
@@ -0,0 +1,45 @@
+<?php
+/*
+ * b1gMail Postfix Transport List Creator
+ * Copyright (c) 2022 b1gMail.eu
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ */
+@ini_set('display_errors',0); // Don't display error messages on screen
+require '../src/serverlib/init.inc.php';
+$domains = GetDomainList();
+function getDomainAliasesFromQuery($res,$domains)
+{
+    while ($row = $res->FetchArray()) {
+        if ($row['saliase'] != '') {
+            $domainList2 = explode(':', $row['saliase']);
+            foreach ($domainList2 as $domain) {
+                if (!in_array($domain, $domains)) {
+                    $domains[] = $domain;
+                }
+            }
+        }
+    }
+    return $domains;
+}
+$res = $db->Query('SELECT saliase FROM {pre}gruppen WHERE saliase IS NOT NULL;'); // Get custom alias domains from groups
+$domains = getDomainAliasesFromQuery($res,$domains);
+$res = $db->Query('SELECT saliase FROM {pre}users WHERE saliase IS NOT NULL;'); // Get custom alias domains from users
+$domains = getDomainAliasesFromQuery($res,$domains);
+
+foreach ($domains as $domain) {
+    echo $domain.' b1gmailtransport:dummy'."\n";
+}