diff --git a/common/kms.tf b/common/kms.tf
index e8df353..3834650 100644
--- a/common/kms.tf
+++ b/common/kms.tf
@@ -4,7 +4,7 @@
 # }
 # 
 locals {
-  kms_key_arn  = var.kms_key_arn == null ? aws_kms_key.key[0].arn : var.kms_key_arn
+  kms_key_arn  = var.kms_key_arn == null ? try(aws_kms_key.key[0].arn, "") : var.kms_key_arn
   kms_key_name = format("%s%s", local._prefixes["kms"], local.name)
 
   kms_admin_root      = [format("arn:%v:iam::%v:root", local.partition, local.account_id)]