diff --git a/src/drivers/sqs/Queue.php b/src/drivers/sqs/Queue.php
index 898ea019a..486c38147 100644
--- a/src/drivers/sqs/Queue.php
+++ b/src/drivers/sqs/Queue.php
@@ -200,7 +200,7 @@ protected function pushMessage($message, $ttr, $delay, $priority)
             'MessageAttributes' => [
                 'TTR' => [
                     'DataType' => 'Number',
-                    'StringValue' => $ttr,
+                    'StringValue' => (string) $ttr,
                 ],
             ],
         ];