diff --git a/test/cpp/client/client_channel_stress_test.cc b/test/cpp/client/client_channel_stress_test.cc
index 91419cb257b..195308c39b0 100644
--- a/test/cpp/client/client_channel_stress_test.cc
+++ b/test/cpp/client/client_channel_stress_test.cc
@@ -268,7 +268,7 @@ class ClientChannelStressTest {
     std::ostringstream uri;
     uri << "fake:///servername_not_used";
     channel_ =
-        CreateCustomChannel(uri.str(), InsecureChannelCredentials(), args);
+        ::grpc::CreateCustomChannel(uri.str(), InsecureChannelCredentials(), args);
     stub_ = grpc::testing::EchoTestService::NewStub(channel_);
   }
 
diff --git a/test/cpp/end2end/async_end2end_test.cc b/test/cpp/end2end/async_end2end_test.cc
index e09f54dcc3f..f8e65ecff41 100644
--- a/test/cpp/end2end/async_end2end_test.cc
+++ b/test/cpp/end2end/async_end2end_test.cc
@@ -295,7 +295,7 @@ class AsyncEnd2endTest : public ::testing::TestWithParam<TestScenario> {
         GetParam().credentials_type, &args);
     std::shared_ptr<Channel> channel =
         !(GetParam().inproc)
-            ? CreateCustomChannel(server_address_.str(), channel_creds, args)
+            ? ::grpc::CreateCustomChannel(server_address_.str(), channel_creds, args)
             : server_->InProcessChannel(args);
     stub_ = grpc::testing::EchoTestService::NewStub(channel);
   }
@@ -1256,7 +1256,7 @@ TEST_P(AsyncEnd2endTest, UnimplementedRpc) {
       GetParam().credentials_type, &args);
   std::shared_ptr<Channel> channel =
       !(GetParam().inproc)
-          ? CreateCustomChannel(server_address_.str(), channel_creds, args)
+          ? ::grpc::CreateCustomChannel(server_address_.str(), channel_creds, args)
           : server_->InProcessChannel(args);
   std::unique_ptr<grpc::testing::UnimplementedEchoService::Stub> stub;
   stub = grpc::testing::UnimplementedEchoService::NewStub(channel);
diff --git a/test/cpp/end2end/channelz_service_test.cc b/test/cpp/end2end/channelz_service_test.cc
index fe52a64db48..26ef59fbeb3 100644
--- a/test/cpp/end2end/channelz_service_test.cc
+++ b/test/cpp/end2end/channelz_service_test.cc
@@ -145,7 +145,7 @@ class ChannelzServerTest : public ::testing::Test {
       ChannelArguments args;
       args.SetInt(GRPC_ARG_ENABLE_CHANNELZ, 1);
       args.SetInt(GRPC_ARG_MAX_CHANNEL_TRACE_EVENT_MEMORY_PER_NODE, 1024);
-      std::shared_ptr<Channel> channel_to_backend = CreateCustomChannel(
+      std::shared_ptr<Channel> channel_to_backend = ::grpc::CreateCustomChannel(
           backend_server_address, InsecureChannelCredentials(), args);
       proxy_service_.AddChannelToBackend(channel_to_backend);
     }
@@ -157,7 +157,7 @@ class ChannelzServerTest : public ::testing::Test {
     // disable channelz. We only want to focus on proxy to backend outbound.
     args.SetInt(GRPC_ARG_ENABLE_CHANNELZ, 0);
     std::shared_ptr<Channel> channel =
-        CreateCustomChannel(target, InsecureChannelCredentials(), args);
+        ::grpc::CreateCustomChannel(target, InsecureChannelCredentials(), args);
     channelz_stub_ = grpc::channelz::v1::Channelz::NewStub(channel);
     echo_stub_ = grpc::testing::EchoTestService::NewStub(channel);
   }
@@ -171,7 +171,7 @@ class ChannelzServerTest : public ::testing::Test {
     // This ensures that gRPC will not do connection sharing.
     args.SetInt("salt", salt++);
     std::shared_ptr<Channel> channel =
-        CreateCustomChannel(target, InsecureChannelCredentials(), args);
+        ::grpc::CreateCustomChannel(target, InsecureChannelCredentials(), args);
     return grpc::testing::EchoTestService::NewStub(channel);
   }
 
diff --git a/test/cpp/end2end/client_callback_end2end_test.cc b/test/cpp/end2end/client_callback_end2end_test.cc
index 821fcc2da6d..cb1d734c800 100644
--- a/test/cpp/end2end/client_callback_end2end_test.cc
+++ b/test/cpp/end2end/client_callback_end2end_test.cc
@@ -143,7 +143,7 @@ class ClientCallbackEnd2endTest
       case Protocol::TCP:
         if (!GetParam().use_interceptors) {
           channel_ =
-              CreateCustomChannel(server_address_.str(), channel_creds, args);
+              ::grpc::CreateCustomChannel(server_address_.str(), channel_creds, args);
         } else {
           channel_ = CreateCustomChannelWithInterceptors(
               server_address_.str(), channel_creds, args,
@@ -1094,7 +1094,7 @@ TEST_P(ClientCallbackEnd2endTest, UnimplementedRpc) {
       GetParam().credentials_type, &args);
   std::shared_ptr<Channel> channel =
       (GetParam().protocol == Protocol::TCP)
-          ? CreateCustomChannel(server_address_.str(), channel_creds, args)
+          ? ::grpc::CreateCustomChannel(server_address_.str(), channel_creds, args)
           : server_->InProcessChannel(args);
   std::unique_ptr<grpc::testing::UnimplementedEchoService::Stub> stub;
   stub = grpc::testing::UnimplementedEchoService::NewStub(channel);
diff --git a/test/cpp/end2end/client_lb_end2end_test.cc b/test/cpp/end2end/client_lb_end2end_test.cc
index 77f9db94acc..b6c4ad7bd2d 100644
--- a/test/cpp/end2end/client_lb_end2end_test.cc
+++ b/test/cpp/end2end/client_lb_end2end_test.cc
@@ -236,7 +236,7 @@ class ClientLbEnd2endTest : public ::testing::Test {
     }  // else, default to pick first
     args.SetPointer(GRPC_ARG_FAKE_RESOLVER_RESPONSE_GENERATOR,
                     response_generator_.get());
-    return CreateCustomChannel("fake:///", creds_, args);
+    return ::grpc::CreateCustomChannel("fake:///", creds_, args);
   }
 
   bool SendRpc(
diff --git a/test/cpp/end2end/end2end_test.cc b/test/cpp/end2end/end2end_test.cc
index 40023c72f62..0b4df97f4cb 100644
--- a/test/cpp/end2end/end2end_test.cc
+++ b/test/cpp/end2end/end2end_test.cc
@@ -341,7 +341,7 @@ class End2endTest : public ::testing::TestWithParam<TestScenario> {
     if (!GetParam().inproc) {
       if (!GetParam().use_interceptors) {
         channel_ =
-            CreateCustomChannel(server_address_.str(), channel_creds, args);
+            ::grpc::CreateCustomChannel(server_address_.str(), channel_creds, args);
       } else {
         channel_ = CreateCustomChannelWithInterceptors(
             server_address_.str(), channel_creds, args,
diff --git a/test/cpp/end2end/grpclb_end2end_test.cc b/test/cpp/end2end/grpclb_end2end_test.cc
index ee8b3e1e52b..7477878faa0 100644
--- a/test/cpp/end2end/grpclb_end2end_test.cc
+++ b/test/cpp/end2end/grpclb_end2end_test.cc
@@ -433,7 +433,7 @@ class GrpclbEnd2endTest : public ::testing::Test {
             channel_creds, call_creds, nullptr)));
     call_creds->Unref();
     channel_creds->Unref();
-    channel_ = CreateCustomChannel(uri.str(), creds, args);
+    channel_ = ::grpc::CreateCustomChannel(uri.str(), creds, args);
     stub_ = grpc::testing::EchoTestService::NewStub(channel_);
   }
 
diff --git a/test/cpp/end2end/shutdown_test.cc b/test/cpp/end2end/shutdown_test.cc
index da42178d67c..9e925364b1f 100644
--- a/test/cpp/end2end/shutdown_test.cc
+++ b/test/cpp/end2end/shutdown_test.cc
@@ -86,7 +86,7 @@ class ShutdownTest : public ::testing::TestWithParam<string> {
     ChannelArguments args;
     auto channel_creds =
         GetCredentialsProvider()->GetChannelCredentials(GetParam(), &args);
-    channel_ = CreateCustomChannel(target, channel_creds, args);
+    channel_ = ::grpc::CreateCustomChannel(target, channel_creds, args);
     stub_ = grpc::testing::EchoTestService::NewStub(channel_);
   }
 
diff --git a/test/cpp/end2end/xds_end2end_test.cc b/test/cpp/end2end/xds_end2end_test.cc
index 11a64264494..04bec5a9ee8 100644
--- a/test/cpp/end2end/xds_end2end_test.cc
+++ b/test/cpp/end2end/xds_end2end_test.cc
@@ -432,7 +432,7 @@ class XdsEnd2endTest : public ::testing::Test {
             channel_creds, call_creds, nullptr)));
     call_creds->Unref();
     channel_creds->Unref();
-    channel_ = CreateCustomChannel(uri.str(), creds, args);
+    channel_ = ::grpc::CreateCustomChannel(uri.str(), creds, args);
     stub_ = grpc::testing::EchoTestService::NewStub(channel_);
   }
 
diff --git a/test/cpp/microbenchmarks/fullstack_fixtures.h b/test/cpp/microbenchmarks/fullstack_fixtures.h
index 6bbf553bbd8..ed231752438 100644
--- a/test/cpp/microbenchmarks/fullstack_fixtures.h
+++ b/test/cpp/microbenchmarks/fullstack_fixtures.h
@@ -87,7 +87,7 @@ class FullstackFixture : public BaseFixture {
     config.ApplyCommonChannelArguments(&args);
     if (address.length() > 0) {
       channel_ =
-          CreateCustomChannel(address, InsecureChannelCredentials(), args);
+          ::grpc::CreateCustomChannel(address, InsecureChannelCredentials(), args);
     } else {
       channel_ = server_->InProcessChannel(args);
     }
diff --git a/test/cpp/util/create_test_channel.cc b/test/cpp/util/create_test_channel.cc
index 79a5e13d993..d036e785360 100644
--- a/test/cpp/util/create_test_channel.cc
+++ b/test/cpp/util/create_test_channel.cc
@@ -118,7 +118,7 @@ std::shared_ptr<Channel> CreateTestChannel(
   if (creds.get()) {
     channel_creds = CompositeChannelCredentials(channel_creds, creds);
   }
-  return CreateCustomChannel(server, channel_creds, channel_args);
+  return ::grpc::CreateCustomChannel(server, channel_creds, channel_args);
 }
 
 std::shared_ptr<Channel> CreateTestChannel(
@@ -132,7 +132,7 @@ std::shared_ptr<Channel> CreateTestChannel(
   std::shared_ptr<ChannelCredentials> channel_creds;
   if (cred_type.empty()) {
     if (interceptor_creators.empty()) {
-      return CreateCustomChannel(server, InsecureChannelCredentials(), args);
+      return ::grpc::CreateCustomChannel(server, InsecureChannelCredentials(), args);
     } else {
       return experimental::CreateCustomChannelWithInterceptors(
           server, InsecureChannelCredentials(), args,
@@ -159,7 +159,7 @@ std::shared_ptr<Channel> CreateTestChannel(
       channel_creds = CompositeChannelCredentials(channel_creds, creds);
     }
     if (interceptor_creators.empty()) {
-      return CreateCustomChannel(connect_to, channel_creds, channel_args);
+      return ::grpc::CreateCustomChannel(connect_to, channel_creds, channel_args);
     } else {
       return experimental::CreateCustomChannelWithInterceptors(
           connect_to, channel_creds, channel_args,
@@ -171,7 +171,7 @@ std::shared_ptr<Channel> CreateTestChannel(
     GPR_ASSERT(channel_creds != nullptr);
 
     if (interceptor_creators.empty()) {
-      return CreateCustomChannel(server, channel_creds, args);
+      return ::grpc::CreateCustomChannel(server, channel_creds, args);
     } else {
       return experimental::CreateCustomChannelWithInterceptors(
           server, channel_creds, args, std::move(interceptor_creators));