diff --git a/modules/iam-service-account/README.md b/modules/iam-service-account/README.md
index a7c0cb0f4..a1b1ed9c7 100644
--- a/modules/iam-service-account/README.md
+++ b/modules/iam-service-account/README.md
@@ -42,7 +42,7 @@ module "myproject-default-service-accounts" {
 | *iam_project_roles* | Project roles granted to the service account, by project id. | <code title="map&#40;list&#40;string&#41;&#41;">map(list(string))</code> |  | <code title="">{}</code> |
 | *iam_storage_roles* | Storage roles granted to the service account, by bucket name. | <code title="map&#40;list&#40;string&#41;&#41;">map(list(string))</code> |  | <code title="">{}</code> |
 | *prefix* | Prefix applied to service account names. | <code title="">string</code> |  | <code title="">null</code> |
-| *public_keys_directory* | Path to public keys data files to upload to the service account (should have `.crt` extension). | <code title="">string</code> |  | <code title=""></code> |
+| *public_keys_directory* | Path to public keys data files to upload to the service account (should have `.pem` extension). | <code title="">string</code> |  | <code title=""></code> |
 | *service_account_create* | Create service account. When set to false, uses a data source to reference an existing service account. | <code title="">bool</code> |  | <code title="">true</code> |
 
 ## Outputs