diff --git a/modules/iam-service-account/README.md b/modules/iam-service-account/README.md
index f12542edb..fb1449b76 100644
--- a/modules/iam-service-account/README.md
+++ b/modules/iam-service-account/README.md
@@ -41,6 +41,7 @@ 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> |
+| *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
 
diff --git a/modules/iam-service-account/main.tf b/modules/iam-service-account/main.tf
index 071d7a14a..2095ec5a1 100644
--- a/modules/iam-service-account/main.tf
+++ b/modules/iam-service-account/main.tf
@@ -57,10 +57,23 @@ locals {
     : map("", null)
   , {})
   prefix             = var.prefix != null ? "${var.prefix}-" : ""
-  resource_iam_email = "serviceAccount:${google_service_account.service_account.email}"
+  resource_iam_email = "serviceAccount:${local.service_account.email}"
+  service_account = (
+    var.service_account_create
+    ? try(google_service_account.service_account.0, null)
+    : try(data.google_service_account.service_account.0, null)
+  )
+}
+
+
+data "google_service_account" "service_account" {
+  count      = var.service_account_create ? 0 : 1
+  project    = var.project_id
+  account_id = "${local.prefix}${var.name}"
 }
 
 resource "google_service_account" "service_account" {
+  count        = var.service_account_create ? 1 : 0
   project      = var.project_id
   account_id   = "${local.prefix}${var.name}"
   display_name = var.display_name
@@ -68,12 +81,12 @@ resource "google_service_account" "service_account" {
 
 resource "google_service_account_key" "key" {
   for_each           = var.generate_key ? { 1 = 1 } : {}
-  service_account_id = google_service_account.service_account.email
+  service_account_id = local.service_account.email
 }
 
 resource "google_service_account_iam_binding" "roles" {
   for_each           = var.iam
-  service_account_id = google_service_account.service_account.name
+  service_account_id = local.service_account.name
   role               = each.key
   members            = each.value
 }
diff --git a/modules/iam-service-account/outputs.tf b/modules/iam-service-account/outputs.tf
index 2b53cc6f7..642cbb89a 100644
--- a/modules/iam-service-account/outputs.tf
+++ b/modules/iam-service-account/outputs.tf
@@ -16,12 +16,12 @@
 
 output "service_account" {
   description = "Service account resource."
-  value       = google_service_account.service_account
+  value       = local.service_account
 }
 
 output "email" {
   description = "Service account email."
-  value       = google_service_account.service_account.email
+  value       = local.service_account.email
 }
 
 output "iam_email" {
diff --git a/modules/iam-service-account/variables.tf b/modules/iam-service-account/variables.tf
index ed32f6167..f3106e884 100644
--- a/modules/iam-service-account/variables.tf
+++ b/modules/iam-service-account/variables.tf
@@ -77,3 +77,9 @@ variable "project_id" {
   description = "Project id where service account will be created."
   type        = string
 }
+
+variable "service_account_create" {
+  description = "Create service account. When set to false, uses a data source to reference an existing service account."
+  type        = bool
+  default     = true
+}