diff --git a/src/compiler/cpp_generator.cc b/src/compiler/cpp_generator.cc
index 4e294961471..763f27e487d 100644
--- a/src/compiler/cpp_generator.cc
+++ b/src/compiler/cpp_generator.cc
@@ -144,6 +144,7 @@ grpc::string GetHeaderIncludes(grpc_generator::File* file,
         "grpcpp/impl/codegen/client_callback.h",
         "grpcpp/impl/codegen/client_context.h",
         "grpcpp/impl/codegen/completion_queue.h",
+        "grpcpp/impl/codegen/message_allocator.h",
         "grpcpp/impl/codegen/method_handler.h",
         "grpcpp/impl/codegen/proto_utils.h",
         "grpcpp/impl/codegen/rpc_method.h",
@@ -159,17 +160,6 @@ grpc::string GetHeaderIncludes(grpc_generator::File* file,
     PrintIncludes(printer.get(), headers, params.use_system_headers,
                   params.grpc_search_path);
     printer->Print(vars, "\n");
-    printer->Print(vars, "namespace grpc_impl {\n");
-    printer->Print(vars, "class CompletionQueue;\n");
-    printer->Print(vars, "class ServerCompletionQueue;\n");
-    printer->Print(vars, "class ServerContext;\n");
-    printer->Print(vars, "}  // namespace grpc_impl\n\n");
-    printer->Print(vars, "namespace grpc {\n");
-    printer->Print(vars, "namespace experimental {\n");
-    printer->Print(vars, "template <typename RequestT, typename ResponseT>\n");
-    printer->Print(vars, "class MessageAllocator;\n");
-    printer->Print(vars, "}  // namespace experimental\n");
-    printer->Print(vars, "}  // namespace grpc\n\n");
 
     vars["message_header_ext"] = params.message_header_extension.empty()
                                      ? kCppGeneratorMessageHeaderExt
@@ -1662,6 +1652,7 @@ grpc::string GetSourceIncludes(grpc_generator::File* file,
         "grpcpp/impl/codegen/channel_interface.h",
         "grpcpp/impl/codegen/client_unary_call.h",
         "grpcpp/impl/codegen/client_callback.h",
+        "grpcpp/impl/codegen/message_allocator.h",
         "grpcpp/impl/codegen/method_handler.h",
         "grpcpp/impl/codegen/rpc_service_method.h",
         "grpcpp/impl/codegen/server_callback.h",
diff --git a/test/cpp/codegen/compiler_test_golden b/test/cpp/codegen/compiler_test_golden
index bd3b2a4c500..02919feaed1 100644
--- a/test/cpp/codegen/compiler_test_golden
+++ b/test/cpp/codegen/compiler_test_golden
@@ -33,6 +33,7 @@
 #include <grpcpp/impl/codegen/client_callback.h>
 #include <grpcpp/impl/codegen/client_context.h>
 #include <grpcpp/impl/codegen/completion_queue.h>
+#include <grpcpp/impl/codegen/message_allocator.h>
 #include <grpcpp/impl/codegen/method_handler.h>
 #include <grpcpp/impl/codegen/proto_utils.h>
 #include <grpcpp/impl/codegen/rpc_method.h>
@@ -44,19 +45,6 @@
 #include <grpcpp/impl/codegen/stub_options.h>
 #include <grpcpp/impl/codegen/sync_stream.h>
 
-namespace grpc_impl {
-class CompletionQueue;
-class ServerCompletionQueue;
-class ServerContext;
-}  // namespace grpc_impl
-
-namespace grpc {
-namespace experimental {
-template <typename RequestT, typename ResponseT>
-class MessageAllocator;
-}  // namespace experimental
-}  // namespace grpc
-
 namespace grpc {
 namespace testing {