diff --git a/lib/Iugu/Utilities.php b/lib/Iugu/Utilities.php
index ff150ce..6080c97 100644
--- a/lib/Iugu/Utilities.php
+++ b/lib/Iugu/Utilities.php
@@ -44,8 +44,8 @@ public static function arrayToParams($array, $prefix = null)
                 $k = $prefix.'[]';
             }
 
-            if (is_array($v)) {
-                $params[] = self::arrayToParams($v, $k);
+            if (is_array($v) || is_object($v)) {
+                $params[] = self::arrayToParams((array)$v, $k);
             } else {
                 $params[] = $k.'='.urlencode($v);
             }