diff --git a/application/Preorder/Preorder.php b/application/Preorder/Preorder.php
index 82a94c73c..7235fbb6d 100644
--- a/application/Preorder/Preorder.php
+++ b/application/Preorder/Preorder.php
@@ -84,7 +84,28 @@ class Preorder extends mfBaseModel {
     }
 
     public function updateRimoWorkorderContact() {
+        $contact_fields = [
+            "company",
+            "uid",
+            "firstname",
+            "lastname",
+            "phone",
+            "email"
+        ];
+        $changed_fields = $this->getChangedFields();
 
+        $update = [];
+        foreach($changed_fields as $field) {
+            if(in_array($field, $contact_fields)) {
+                $update[$field] = $this->data->$field;
+            }
+        }
+
+        foreach($this->getProperty("adb_wohneinheit")->rimo_workorders as $workorder) {
+            Rimoapi::updateWorkorder($workorder->rimo_id, $update);
+        }
+
+        return true;
     }
 
     public function createHistoryEntry() {
diff --git a/lib/Rimoapi/Rimoapi.php b/lib/Rimoapi/Rimoapi.php
index e60e56118..2ad4a2b1c 100644
--- a/lib/Rimoapi/Rimoapi.php
+++ b/lib/Rimoapi/Rimoapi.php
@@ -180,4 +180,62 @@ class Rimoapi {
         $resp_data = json_decode($response);
         return $resp_data;
     }
+
+    public static function updateWorkorder($rimo_id, Array $data = []) {
+        $log = mfLoghandler::singleton();
+
+        if(!$rimo_id || !count($data)) {
+            $log->debug(__METHOD__.": no rimo id or no update data");
+            return false;
+        }
+
+        $contact_fields = [
+            "company" => "company",
+            "firstname" => "firstName",
+            "lastname" => "lastName",
+            "phone" => "phone",
+            "email" => "email"
+        ];
+
+        $update_data = [];
+
+        foreach($data as $field => $value) {
+            if(array_key_exists($field, $contact_fields)) {
+                $update_data[$contact_fields[$field]] = $value;
+            }
+        }
+
+        var_dump($update_data);
+        if(!count($update_data)) {
+            $log->debug(__METHOD__.": no valid update data");
+            return false;
+        }
+
+        $update_data["orderId"] = $rimo_id;
+        $update_data['apiKey'] = RIMO_API_JSON_APIKEY;
+
+        $ctx_opts = [
+            'http' => [
+                'method' => 'PUT',
+                'header' => 'accept: application/json'
+            ]
+        ];
+
+        $qs = http_build_query($update_data);
+
+        $updateWorkorderEp = RIMO_API_JSON_URL.RIMO_API_JSON_EP_UPDATE_WORKORDER;
+        $put_url = $updateWorkorderEp."?".$qs;
+
+        $ctx = stream_context_create($ctx_opts);
+        $log->debug(__METHOD__.": Updating Workorder Contact $rimo_id: $put_url");
+        $response = file_get_contents($put_url, false, $ctx);
+
+        if($response === false) {
+            $log->error("Fehler beim Updaten der Workorder $rimo_id in RIMO");
+            return false;
+        }
+
+        $resp_data = json_decode($response);
+        return $resp_data;
+    }
 }
\ No newline at end of file