diff --git a/resource_compute_backend_service_test.go b/resource_compute_backend_service_test.go
index 133b91d8..7cb1a93e 100644
--- a/resource_compute_backend_service_test.go
+++ b/resource_compute_backend_service_test.go
@@ -217,7 +217,7 @@ func TestAccComputeBackendService_withSessionAffinity(t *testing.T) {
 	})
 
 	if svc.SessionAffinity != "GENERATED_COOKIE" {
-		t.Errorf("Expected SessionAffinity == \"GENERATED_COOKIE\", got %t", svc.SessionAffinity)
+		t.Errorf("Expected SessionAffinity == \"GENERATED_COOKIE\", got %s", svc.SessionAffinity)
 	}
 }