diff --git a/google/cloud/storage/client_options.cc b/google/cloud/storage/client_options.cc
index 2e2cb2c9f885..9c6d56f2856b 100644
--- a/google/cloud/storage/client_options.cc
+++ b/google/cloud/storage/client_options.cc
@@ -22,6 +22,7 @@
 #include "google/cloud/internal/populate_common_options.h"
 #include "google/cloud/internal/rest_options.h"
 #include "google/cloud/internal/rest_response.h"
+#include "google/cloud/internal/service_endpoint.h"
 #include "google/cloud/log.h"
 #include "absl/strings/str_split.h"
 #include <cstdlib>
@@ -169,11 +170,16 @@ Options ApplyPolicy(Options opts, IdempotencyPolicy const& p) {
 
 Options DefaultOptions(std::shared_ptr<oauth2::Credentials> credentials,
                        Options opts) {
+  auto gcs_ep = google::cloud::internal::UniverseDomainEndpoint(
+      "https://storage.googleapis.com", opts);
+  auto iam_ep = absl::StrCat(google::cloud::internal::UniverseDomainEndpoint(
+                                 "https://iamcredentials.googleapis.com", opts),
+                             "/v1");
   auto o =
       Options{}
           .set<Oauth2CredentialsOption>(std::move(credentials))
-          .set<RestEndpointOption>("https://storage.googleapis.com")
-          .set<IamEndpointOption>("https://iamcredentials.googleapis.com/v1")
+          .set<RestEndpointOption>(std::move(gcs_ep))
+          .set<IamEndpointOption>(std::move(iam_ep))
           .set<TargetApiVersionOption>("v1")
           .set<ConnectionPoolSizeOption>(DefaultConnectionPoolSize())
           .set<DownloadBufferSizeOption>(
diff --git a/google/cloud/storage/client_options_test.cc b/google/cloud/storage/client_options_test.cc
index b78caf22e6e1..85f7e9142982 100644
--- a/google/cloud/storage/client_options_test.cc
+++ b/google/cloud/storage/client_options_test.cc
@@ -22,6 +22,7 @@
 #include "google/cloud/testing_util/scoped_environment.h"
 #include "google/cloud/testing_util/setenv.h"
 #include "google/cloud/testing_util/status_matchers.h"
+#include "google/cloud/universe_domain_options.h"
 #include <gmock/gmock.h>
 #include <cstdlib>
 #include <fstream>
@@ -390,6 +391,30 @@ TEST_F(ClientOptionsTest, DefaultOptions) {
   EXPECT_FALSE(o.has<rest::CAPathOption>());
 }
 
+TEST_F(ClientOptionsTest, IncorporatesUniverseDomain) {
+  auto o = internal::DefaultOptions(
+      oauth2::CreateAnonymousCredentials(),
+      Options{}.set<google::cloud::internal::UniverseDomainOption>(
+          "my-ud.net"));
+  EXPECT_EQ(o.get<RestEndpointOption>(), "https://storage.my-ud.net");
+  EXPECT_EQ(o.get<IamEndpointOption>(), "https://iamcredentials.my-ud.net/v1");
+}
+
+TEST_F(ClientOptionsTest, CustomEndpointOverridesUniverseDomain) {
+  auto o = internal::DefaultOptions(
+      oauth2::CreateAnonymousCredentials(),
+      Options{}
+          .set<RestEndpointOption>("https://custom-storage.googleapis.com")
+          .set<IamEndpointOption>(
+              "https://custom-iamcredentials.googleapis.com/v1")
+          .set<google::cloud::internal::UniverseDomainOption>(
+              "ignored-ud.net"));
+  EXPECT_EQ(o.get<RestEndpointOption>(),
+            "https://custom-storage.googleapis.com");
+  EXPECT_EQ(o.get<IamEndpointOption>(),
+            "https://custom-iamcredentials.googleapis.com/v1");
+}
+
 TEST_F(ClientOptionsTest, HttpVersion) {
   namespace rest = ::google::cloud::rest_internal;
   auto const options = internal::DefaultOptions(