diff --git a/pc/peer_connection.cc b/pc/peer_connection.cc
index 9c4461d9ec..6a5f925732 100644
--- a/pc/peer_connection.cc
+++ b/pc/peer_connection.cc
@@ -3060,6 +3060,18 @@ static RTCError UpdateSimulcastLayerStatusInSender(
   return result;
 }
 
+static bool SimulcastIsRejected(
+    const ContentInfo* local_content,
+    const MediaContentDescription& answer_media_desc) {
+  bool simulcast_offered = local_content &&
+                           local_content->media_description() &&
+                           local_content->media_description()->HasSimulcast();
+  bool simulcast_answered = answer_media_desc.HasSimulcast();
+  bool rids_supported = RtpExtension::FindHeaderExtensionByUri(
+      answer_media_desc.rtp_header_extensions(), RtpExtension::kRidUri);
+  return simulcast_offered && (!simulcast_answered || !rids_supported);
+}
+
 static RTCError DisableSimulcastInSender(
     rtc::scoped_refptr<RtpSenderInternal> sender) {
   RTC_DCHECK(sender);
@@ -3155,12 +3167,7 @@ PeerConnection::AssociateTransceiver(cricket::ContentSource source,
 
     // Check if the offer indicated simulcast but the answer rejected it.
     // This can happen when simulcast is not supported on the remote party.
-    // This check can be simplified to comparing the number of send encodings,
-    // but that might break legacy implementation in which simulcast is not
-    // signaled in the remote description.
-    if (old_local_content && old_local_content->media_description() &&
-        old_local_content->media_description()->HasSimulcast() &&
-        !media_desc->HasSimulcast()) {
+    if (SimulcastIsRejected(old_local_content, *media_desc)) {
       RTCError error =
           DisableSimulcastInSender(transceiver->internal()->sender_internal());
       if (!error.ok()) {
diff --git a/pc/peer_connection_simulcast_unittest.cc b/pc/peer_connection_simulcast_unittest.cc
index 07e079a2a3..6fa4bae403 100644
--- a/pc/peer_connection_simulcast_unittest.cc
+++ b/pc/peer_connection_simulcast_unittest.cc
@@ -113,7 +113,7 @@ class PeerConnectionSimulcastTests : public testing::Test {
                            const std::vector<SimulcastLayer>& answer_layers) {
     auto offer = local->CreateOfferAndSetAsLocal();
     // Remove simulcast as the second peer connection won't support it.
-    auto removed_simulcast = RemoveSimulcast(offer.get());
+    RemoveSimulcast(offer.get());
     std::string err;
     EXPECT_TRUE(remote->SetRemoteDescription(std::move(offer), &err)) << err;
     auto answer = remote->CreateAnswerAndSetAsLocal();
@@ -461,4 +461,38 @@ TEST_F(PeerConnectionSimulcastTests,
   EXPECT_TRUE(ValidateTransceiverParameters(transceiver, expected_layers));
 }
 
+TEST_F(PeerConnectionSimulcastTests, NegotiationDoesNotHaveRidExtension) {
+  auto local = CreatePeerConnectionWrapper();
+  auto remote = CreatePeerConnectionWrapper();
+  auto layers = CreateLayers({"1", "2", "3"}, true);
+  auto expected_layers = CreateLayers({"1"}, true);
+  auto transceiver = AddTransceiver(local.get(), layers);
+  auto offer = local->CreateOfferAndSetAsLocal();
+  // Remove simulcast as the second peer connection won't support it.
+  RemoveSimulcast(offer.get());
+  std::string err;
+  EXPECT_TRUE(remote->SetRemoteDescription(std::move(offer), &err)) << err;
+  auto answer = remote->CreateAnswerAndSetAsLocal();
+  // Setup the answer to look like a server response.
+  // Drop the RID header extension.
+  auto mcd_answer = answer->description()->contents()[0].media_description();
+  auto& receive_layers = mcd_answer->simulcast_description().receive_layers();
+  for (const SimulcastLayer& layer : layers) {
+    receive_layers.AddLayer(layer);
+  }
+  cricket::RtpHeaderExtensions extensions;
+  for (auto extension : mcd_answer->rtp_header_extensions()) {
+    if (extension.uri != RtpExtension::kRidUri) {
+      extensions.push_back(extension);
+    }
+  }
+  mcd_answer->set_rtp_header_extensions(extensions);
+  EXPECT_EQ(layers.size(), mcd_answer->simulcast_description()
+                               .receive_layers()
+                               .GetAllLayers()
+                               .size());
+  EXPECT_TRUE(local->SetRemoteDescription(std::move(answer), &err)) << err;
+  EXPECT_TRUE(ValidateTransceiverParameters(transceiver, expected_layers));
+}
+
 }  // namespace webrtc