diff --git a/htdocs/fourn/commande/list.php b/htdocs/fourn/commande/list.php
index 2fb6f03607a..b2b6484917d 100644
--- a/htdocs/fourn/commande/list.php
+++ b/htdocs/fourn/commande/list.php
@@ -274,6 +274,8 @@ if (empty($reshook)) {
 
 		$db->begin();
 
+		$default_ref_supplier=dol_print_date(dol_now(), '%Y%m%d%H%M%S');
+
 		foreach ($orders as $id_order) {
 			$cmd = new CommandeFournisseur($db);
 			if ($cmd->fetch($id_order) <= 0) {
@@ -291,7 +293,7 @@ if (empty($reshook)) {
 				$objecttmp->fk_project = $cmd->fk_project;
 				$objecttmp->multicurrency_code = $cmd->multicurrency_code;
 				if (empty($createbills_onebythird)) {
-					$objecttmp->ref_supplier = !empty($cmd->ref_supplier) ? $cmd->ref_supplier : dol_print_date(dol_now(), '%Y%m%d%H%M%S');
+					$objecttmp->ref_supplier = !empty($cmd->ref_supplier) ? $cmd->ref_supplier : $default_ref_supplier+1;
 				}
 
 				$datefacture = dol_mktime(12, 0, 0, GETPOST('remonth', 'int'), GETPOST('reday', 'int'), GETPOST('reyear', 'int'));