diff --git a/google-cloud-iamcredentials/src/main/java/com/google/cloud/iam/credentials/v1/stub/IamCredentialsStubSettings.java b/google-cloud-iamcredentials/src/main/java/com/google/cloud/iam/credentials/v1/stub/IamCredentialsStubSettings.java
index 0cec2d96..7a4cd497 100644
--- a/google-cloud-iamcredentials/src/main/java/com/google/cloud/iam/credentials/v1/stub/IamCredentialsStubSettings.java
+++ b/google-cloud-iamcredentials/src/main/java/com/google/cloud/iam/credentials/v1/stub/IamCredentialsStubSettings.java
@@ -138,6 +138,11 @@ public static String getDefaultEndpoint() {
     return "iamcredentials.googleapis.com:443";
   }
 
+  /** Returns the default mTLS service endpoint. */
+  public static String getDefaultMtlsEndpoint() {
+    return "iamcredentials.mtls.googleapis.com:443";
+  }
+
   /** Returns the default service scopes. */
   public static List<String> getDefaultServiceScopes() {
     return DEFAULT_SERVICE_SCOPES;
@@ -277,6 +282,8 @@ private static Builder createDefault() {
       builder.setCredentialsProvider(defaultCredentialsProviderBuilder().build());
       builder.setInternalHeaderProvider(defaultApiClientHeaderProviderBuilder().build());
       builder.setEndpoint(getDefaultEndpoint());
+      builder.setMtlsEndpoint(getDefaultMtlsEndpoint());
+      builder.setSwitchToMtlsEndpointAllowed(true);
 
       return initDefaults(builder);
     }
diff --git a/synth.metadata b/synth.metadata
index 40b35cb3..f62df3b5 100644
--- a/synth.metadata
+++ b/synth.metadata
@@ -4,15 +4,15 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-iamcredentials.git",
-        "sha": "af541729d83d8dbaa463ccae92cadb488202933a"
+        "sha": "692f90d0b5ecc5f4b758699bdf8ec13d8dd56273"
       }
     },
     {
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "9e3105549a35520f215359065c11e8dce15e18af",
-        "internalRef": "378266372"
+        "sha": "08c4eeb531c01ad031134dca94b18e3f7dd35902",
+        "internalRef": "378718217"
       }
     },
     {