diff --git a/application/Api/v1/PreorderApicontroller.php b/application/Api/v1/PreorderApicontroller.php
index f21e991e6..3d423fb41 100644
--- a/application/Api/v1/PreorderApicontroller.php
+++ b/application/Api/v1/PreorderApicontroller.php
@@ -456,7 +456,7 @@ class PreorderApicontroller extends mfBaseApicontroller {
     /*
      * get customer data
      */
-    foreach(['company','uid','firstname','lastname','street','housenumber','zip','city','phone','email','block','stiege','stock','tuer'] as $key) {
+    foreach(['company','uid','firstname','lastname','street','housenumber','zip','city','phone','email','block','stiege','stock','tuer', 'unit_string'] as $key) {
       if(property_exists($customer, $key)) {
         $preorder_data[$key] = ($customer->$key) ? $customer->$key : null;
       }
diff --git a/application/Preorder/PreorderModel.php b/application/Preorder/PreorderModel.php
index caee40441..ad86326f9 100644
--- a/application/Preorder/PreorderModel.php
+++ b/application/Preorder/PreorderModel.php
@@ -39,6 +39,7 @@ class PreorderModel {
   public $stiege;
   public $stock;
   public $tuer;
+  public $unit_string;
   public $zip;
   public $city;
   public $phone;
diff --git a/public/docs/preorder-api.yaml b/public/docs/preorder-api.yaml
index d3d4aa604..edad69279 100644
--- a/public/docs/preorder-api.yaml
+++ b/public/docs/preorder-api.yaml
@@ -1002,6 +1002,10 @@ components:
               type: string
               description: Adresszusatz
               example: null
+            unit_string:
+              type: string
+              description: Zusatzangaben zur Identifizierung der Wohneinheit in einem String. Kann statt den Einzelfeldern (Block, Stiege, Stock, Tür) angegeben werden
+              example: Stg. 2 Stock 3 Tür 7
             phone:
               type: string
               description: Telefonnummer Kunde