diff --git a/source/common/upstream/cluster_manager_impl.h b/source/common/upstream/cluster_manager_impl.h
index 9586357bc4aa1..4cb0914ee20c4 100644
--- a/source/common/upstream/cluster_manager_impl.h
+++ b/source/common/upstream/cluster_manager_impl.h
@@ -203,9 +203,12 @@ class ClusterManagerImpl : public ClusterManager, Logger::Loggable<Logger::Id::u
   Http::AsyncClient& httpAsyncClientForCluster(const std::string& cluster) override;
   bool removeCluster(const std::string& cluster) override;
   void shutdown() override {
+    // Make sure we destroy all potential outgoing connections before this returns.
     cds_api_.reset();
     ads_mux_.reset();
     active_clusters_.clear();
+    warming_clusters_.clear();
+    updateGauges();
   }
 
   const envoy::api::v2::core::BindConfig& bindConfig() const override { return bind_config_; }
diff --git a/test/common/upstream/cluster_manager_impl_test.cc b/test/common/upstream/cluster_manager_impl_test.cc
index a15b364c8b2d6..c826b50cea322 100644
--- a/test/common/upstream/cluster_manager_impl_test.cc
+++ b/test/common/upstream/cluster_manager_impl_test.cc
@@ -1107,6 +1107,34 @@ TEST_F(ClusterManagerImplTest, RemoveWarmingCluster) {
   EXPECT_TRUE(Mock::VerifyAndClearExpectations(cluster1.get()));
 }
 
+// Verify that shutting down the cluster manager destroys warming clusters.
+TEST_F(ClusterManagerImplTest, ShutdownWithWarming) {
+  const std::string json = R"EOF(
+  {
+    "clusters": []
+  }
+  )EOF";
+
+  create(parseBootstrapFromJson(json));
+
+  InSequence s;
+  ReadyWatcher initialized;
+  EXPECT_CALL(initialized, ready());
+  cluster_manager_->setInitializedCb([&]() -> void { initialized.ready(); });
+
+  std::shared_ptr<MockClusterMockPrioritySet> cluster1(new NiceMock<MockClusterMockPrioritySet>());
+  EXPECT_CALL(factory_, clusterFromProto_(_, _, _, _)).WillOnce(Return(cluster1));
+  EXPECT_CALL(*cluster1, initializePhase()).Times(0);
+  EXPECT_CALL(*cluster1, initialize(_));
+  EXPECT_TRUE(cluster_manager_->addOrUpdateCluster(defaultStaticCluster("fake_cluster"), "version1",
+                                                   dummyWarmingCb));
+  checkStats(1 /*added*/, 0 /*modified*/, 0 /*removed*/, 0 /*active*/, 1 /*warming*/);
+  cluster_manager_->shutdown();
+  checkStats(1 /*added*/, 0 /*modified*/, 0 /*removed*/, 0 /*active*/, 0 /*warming*/);
+
+  EXPECT_TRUE(Mock::VerifyAndClearExpectations(cluster1.get()));
+}
+
 TEST_F(ClusterManagerImplTest, DynamicAddRemove) {
   const std::string json = R"EOF(
   {