diff --git a/test/cpp/util/test_credentials_provider.cc b/test/cpp/util/test_credentials_provider.cc
index 69651700feb8429a024e29075bbadadee82845cf..1086e14258b0c54c69a649a0507a0f655246227b 100644
--- a/test/cpp/util/test_credentials_provider.cc
+++ b/test/cpp/util/test_credentials_provider.cc
@@ -39,6 +39,8 @@
 namespace grpc {
 namespace testing {
 
+const char kTlsCredentialsType[] = "TLS_CREDENTIALS";
+
 std::shared_ptr<ChannelCredentials> GetChannelCredentials(
     const grpc::string& type, ChannelArguments* args) {
   if (type == kInsecureCredentialsType) {
diff --git a/test/cpp/util/test_credentials_provider.h b/test/cpp/util/test_credentials_provider.h
index f4105d94b830ff4ff2f2373d04cefd1137240bb3..f7253051a97dd7c3f6f296a0ee77ccaec717708e 100644
--- a/test/cpp/util/test_credentials_provider.h
+++ b/test/cpp/util/test_credentials_provider.h
@@ -44,7 +44,6 @@ namespace grpc {
 namespace testing {
 
 const char kInsecureCredentialsType[] = "INSECURE_CREDENTIALS";
-const char kTlsCredentialsType[] = "TLS_CREDENTIALS";
 
 // Provide channel credentials according to the given type. Alter the channel
 // arguments if needed.