diff --git a/htdocs/compta/bank/card.php b/htdocs/compta/bank/card.php
index 1f55698d13f03..c23c1b2f96b88 100644
--- a/htdocs/compta/bank/card.php
+++ b/htdocs/compta/bank/card.php
@@ -99,7 +99,7 @@
     $object->owner_address   = trim($_POST["owner_address"]);
 
 	$account_number 		 = GETPOST('account_number','alpha');
-	if ($account_number <= 0) { $object->account_number = ''; } else { $object->account_number = $account_number; }
+	if (empty($account_number) || $account_number == '-1') { $object->account_number = ''; } else { $object->account_number = $account_number; }
 	$fk_accountancy_journal  = GETPOST('fk_accountancy_journal','int');
 	if ($fk_accountancy_journal <= 0) { $object->fk_accountancy_journal = ''; } else { $object->fk_accountancy_journal = $fk_accountancy_journal; }