diff --git a/galette/lib/Galette/Entity/Contribution.php b/galette/lib/Galette/Entity/Contribution.php
index a6c768548..a567a66f6 100644
--- a/galette/lib/Galette/Entity/Contribution.php
+++ b/galette/lib/Galette/Entity/Contribution.php
@@ -962,7 +962,7 @@ public static function setTransactionPart(Db $zdb, int $trans_id, int $contrib_i
      */
     public function isFee(): bool
     {
-        return $this->is_cotis;
+        return $this->is_cotis ?? false;
     }
 
     /**