diff --git a/functions.tf b/functions.tf
index 7ccabd84908dae3f8d2d973268726cb3b5922f8c..9b6b9a01f727a953da4170cc28b71c02ee401202 100644
--- a/functions.tf
+++ b/functions.tf
@@ -75,7 +75,7 @@ resource "aws_iam_role_policy_attachment" "function" {
 }
 
 variable "runtime" {
-  default     = "python3.8"
+  default     = "python3.9"
   description = "The Lambda function runtime."
   type        = string
 }