diff --git a/htdocs/compta/facture/class/api_invoices.class.php b/htdocs/compta/facture/class/api_invoices.class.php
index 1e0392bf452..f41a2ee9ae0 100644
--- a/htdocs/compta/facture/class/api_invoices.class.php
+++ b/htdocs/compta/facture/class/api_invoices.class.php
@@ -508,8 +508,14 @@ class Invoices extends DolibarrApi
               $request_data->fk_parent_line = 0;
       }
 
-      // calculate pa_ht
-      $marginInfos = getMarginInfos($request_data->subprice, $request_data->remise_percent, $request_data->tva_tx, $request_data->localtax1_tx, $request_data->localtax2_tx, $request_data->fk_fournprice, $request_data->pa_ht);
+      $pa_ht = $request_data->pa_ht;
+
+      // calculate pa_ht  
+      if ($pa_ht == 'auto')
+      {
+          $marginInfos = getMarginInfos($request_data->subprice, $request_data->remise_percent, $request_data->tva_tx, $request_data->localtax1_tx, $request_data->localtax2_tx, $request_data->fk_fournprice, $request_data->pa_ht);
+          $pa_ht = $marginInfos[0];
+      }
 
       $updateRes = $this->invoice->addline(
                               $request_data->desc,
@@ -534,7 +540,7 @@ class Invoices extends DolibarrApi
                               $id,
                               $request_data->fk_parent_line,
                               $request_data->fk_fournprice,
-                              $marginInfos[0],
+                              $pa_ht,
                               $request_data->label,
                               $request_data->array_options,
                               $request_data->situation_percent,