diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index 34bc696f604..10d82b5683d 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -10440,7 +10440,7 @@ function getCommonSubstitutionArray($outputlangs, $onlykey = 0, $exclude = null,
 					$typeforonlinepayment = 'ficheinter';
 				}
 
-				$url = getOnlinePaymentUrl(0, $typeforonlinepayment, $substitutionarray['__REF__'], $amounttouse);
+				$url = getOnlinePaymentUrl(0, $typeforonlinepayment, $substitutionarray['__REF__'], (float) $amounttouse);
 				$paymenturl = $url;
 			}