diff --git a/.changeset/fluffy-seas-behave.md b/.changeset/fluffy-seas-behave.md
new file mode 100644
index 00000000000..073429be5d8
--- /dev/null
+++ b/.changeset/fluffy-seas-behave.md
@@ -0,0 +1,5 @@
+---
+"@firebase/auth": patch
+---
+
+Explicitly set createdAt and lastLoginAt when cloning UserImpl
diff --git a/packages/auth/src/core/user/user_impl.test.ts b/packages/auth/src/core/user/user_impl.test.ts
index 839dc104547..fc0361d8f59 100644
--- a/packages/auth/src/core/user/user_impl.test.ts
+++ b/packages/auth/src/core/user/user_impl.test.ts
@@ -274,7 +274,9 @@ describe('core/user/user_impl', () => {
             uid: 'i-am-uid'
           }
         ],
-        tenantId: 'tenant-id'
+        tenantId: 'tenant-id',
+        createdAt: '2018-01-01 13:02:56.12345678',
+        lastLoginAt: '2018-01-05 13:02:56.12345678'
       });
 
       const newAuth = await testAuth();
@@ -294,6 +296,7 @@ describe('core/user/user_impl', () => {
           uid: 'i-am-uid'
         }
       ]);
+      expect(copy.metadata.toJSON()).to.eql(user.metadata.toJSON());
     });
   });
 });
diff --git a/packages/auth/src/core/user/user_impl.ts b/packages/auth/src/core/user/user_impl.ts
index 65130dffe73..44192cc4617 100644
--- a/packages/auth/src/core/user/user_impl.ts
+++ b/packages/auth/src/core/user/user_impl.ts
@@ -140,11 +140,13 @@ export class UserImpl implements UserInternal {
   }
 
   _clone(auth: AuthInternal): UserInternal {
-    return new UserImpl({
+    const newUser = new UserImpl({
       ...this,
       auth,
       stsTokenManager: this.stsTokenManager._clone()
     });
+    newUser.metadata._copy(this.metadata);
+    return newUser;
   }
 
   _onReload(callback: NextFn<APIUserInfo>): void {