diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertiser.java b/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertiser.java
index 54f7ca3f96..c3306bd3b9 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertiser.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsAdvertiser.java
@@ -1007,6 +1007,19 @@ public class MdnsAdvertiser {
         });
     }
 
+    private List<String> getOffloadSubtype(@NonNull NsdServiceInfo nsdServiceInfo) {
+        // Workaround: Google Cast doesn't announce subtypes per DNS-SD/mDNS spec.
+        // Thus, subtypes aren't offloaded; only "_googlecast._tcp" is.
+        // Subtype responses occur when hardware offload is off.
+        // This solution works because Google Cast doesn't follow the intended usage of subtypes in
+        // the spec, as it always discovers for both the subtype+base type, and only uses the mDNS
+        // subtype as an optimization.
+        if (nsdServiceInfo.getServiceType().equals("_googlecast._tcp")) {
+            return new ArrayList<>();
+        }
+        return new ArrayList<>(nsdServiceInfo.getSubtypes());
+    }
+
     private OffloadServiceInfoWrapper createOffloadService(int serviceId,
             @NonNull Registration registration, byte[] rawOffloadPacket) {
         final NsdServiceInfo nsdServiceInfo = registration.getServiceInfo();
@@ -1017,7 +1030,7 @@ public class MdnsAdvertiser {
         final OffloadServiceInfo offloadServiceInfo = new OffloadServiceInfo(
                 new OffloadServiceInfo.Key(nsdServiceInfo.getServiceName(),
                         nsdServiceInfo.getServiceType()),
-                new ArrayList<>(nsdServiceInfo.getSubtypes()),
+                getOffloadSubtype(nsdServiceInfo),
                 String.join(".", mDeviceHostName),
                 rawOffloadPacket,
                 priority,
diff --git a/tests/unit/java/com/android/server/connectivity/mdns/MdnsAdvertiserTest.kt b/tests/unit/java/com/android/server/connectivity/mdns/MdnsAdvertiserTest.kt
index c733e6a202..e6e6ecca7c 100644
--- a/tests/unit/java/com/android/server/connectivity/mdns/MdnsAdvertiserTest.kt
+++ b/tests/unit/java/com/android/server/connectivity/mdns/MdnsAdvertiserTest.kt
@@ -92,6 +92,13 @@ private val SERVICE_1 = NsdServiceInfo("TestServiceName", "_advertisertest._tcp"
     network = TEST_NETWORK_1
 }
 
+private val GOOGLECAST_SERVICE = NsdServiceInfo("TestServiceName", "_googlecast._tcp").apply {
+    subtypes = setOf(TEST_SUBTYPE)
+    port = 12345
+    hostAddresses = listOf(TEST_ADDR)
+    network = TEST_NETWORK_1
+}
+
 private val SERVICE_1_SUBTYPE = NsdServiceInfo("TestServiceName", "_advertisertest._tcp").apply {
     subtypes = setOf(TEST_SUBTYPE)
     port = 12345
@@ -143,6 +150,15 @@ private val OFFLOAD_SERVICEINFO = OffloadServiceInfo(
     OffloadEngine.OFFLOAD_TYPE_REPLY.toLong()
 )
 
+private val OFFLOAD_SERVICE_INFO_GOOGLECAST = OffloadServiceInfo(
+    OffloadServiceInfo.Key("TestServiceName", "_googlecast._tcp"),
+    listOf(),
+    "Android_test.local",
+    TEST_OFFLOAD_PACKET1,
+    Int.MAX_VALUE,
+    OffloadEngine.OFFLOAD_TYPE_REPLY.toLong()
+)
+
 private val OFFLOAD_SERVICEINFO_NO_SUBTYPE = OffloadServiceInfo(
     OffloadServiceInfo.Key("TestServiceName", "_advertisertest._tcp"),
     listOf(),
@@ -507,6 +523,44 @@ class MdnsAdvertiserTest {
         )))
     }
 
+    @Test
+    fun testAddService_NoSubtypeForGoogleCastOffload() {
+        val advertiser =
+            MdnsAdvertiser(thread.looper, socketProvider, cb, mockDeps, sharedlog, flags, context)
+        postSync {
+            advertiser.addOrUpdateService(
+                SERVICE_ID_1,
+                GOOGLECAST_SERVICE,
+                DEFAULT_ADVERTISING_OPTION,
+                TEST_CLIENT_UID_1
+            )
+        }
+        val socketCbCaptor = ArgumentCaptor.forClass(SocketCallback::class.java)
+        verify(socketProvider).requestSocket(eq(SERVICE_1.network), socketCbCaptor.capture())
+
+        val socketCb = socketCbCaptor.value
+        postSync { socketCb.onSocketCreated(TEST_SOCKETKEY_1, mockSocket1, listOf(TEST_LINKADDR)) }
+
+        val intAdvCbCaptor1 = ArgumentCaptor.forClass(MdnsInterfaceAdvertiser.Callback::class.java)
+        verify(mockDeps).makeAdvertiser(
+            eq(mockSocket1),
+            eq(listOf(TEST_LINKADDR)),
+            eq(thread.looper),
+            any(),
+            intAdvCbCaptor1.capture(),
+            eq(TEST_HOSTNAME),
+            any(),
+            any()
+        )
+
+        doReturn(false).`when`(mockInterfaceAdvertiser1).isProbing(SERVICE_ID_1)
+        postSync {
+            intAdvCbCaptor1.value.onServiceProbingSucceeded(mockInterfaceAdvertiser1, SERVICE_ID_1)
+        }
+
+        verify(cb).onOffloadStartOrUpdate(eq(TEST_INTERFACE1), eq(OFFLOAD_SERVICE_INFO_GOOGLECAST))
+    }
+
     @Test
     fun testAddService_Conflicts() {
         val advertiser =