diff --git a/client-ts/Microsoft.AspNetCore.Client.SignalR.TS.Tests/HubConnection.spec.ts b/client-ts/Microsoft.AspNetCore.Client.SignalR.TS.Tests/HubConnection.spec.ts
new file mode 100644
index 0000000000..9d9c8fcae8
--- /dev/null
+++ b/client-ts/Microsoft.AspNetCore.Client.SignalR.TS.Tests/HubConnection.spec.ts
@@ -0,0 +1,75 @@
+import { IConnection } from "../Microsoft.AspNetCore.SignalR.Client.TS/IConnection"
+import { HubConnection } from "../Microsoft.AspNetCore.SignalR.Client.TS/HubConnection"
+import { DataReceived, ConnectionClosed } from "../Microsoft.AspNetCore.SignalR.Client.TS/Common"
+
+describe("HubConnection", () => {
+    it("completes pending invocations when stopped", async (done) => {
+        let connection: IConnection = {
+            start(transportName: string): Promise<void> {
+                return Promise.resolve();
+            },
+
+            send(data: any): Promise<void> {
+                return Promise.resolve();
+            },
+
+            stop(): void {
+                if (this.onClosed) {
+                    this.onClosed();
+                }
+            },
+
+            onDataReceived: null,
+            onClosed: null
+        };
+
+        let hubConnection = new HubConnection(connection);
+        var invokePromise = hubConnection.invoke("testMethod");
+        hubConnection.stop();
+        invokePromise
+            .then(() => {
+                fail();
+                done();
+            })
+            .catch((error: Error) => {
+                expect(error.message).toBe("Invocation cancelled due to connection being closed.");
+                done();
+            });
+    });
+
+    it("completes pending invocations when connection is lost", async (done) => {
+        let connection: IConnection = {
+            start(transportName: string): Promise<void> {
+                return Promise.resolve();
+            },
+
+            send(data: any): Promise<void> {
+                return Promise.resolve();
+            },
+
+            stop(): void {
+                if (this.onClosed) {
+                    this.onClosed();
+                }
+            },
+
+            onDataReceived: null,
+            onClosed: null
+        };
+
+        let hubConnection = new HubConnection(connection);
+        var invokePromise = hubConnection.invoke("testMethod");
+        invokePromise
+            .then(() => {
+                fail();
+                done();
+            })
+            .catch((error: Error) => {
+                expect(error.message).toBe("Connection lost");
+                done();
+            });
+
+        // Typically this would be called by the transport
+        connection.onClosed(new Error("Connection lost"));
+    });
+});
\ No newline at end of file
diff --git a/client-ts/Microsoft.AspNetCore.SignalR.Client.TS/HubConnection.ts b/client-ts/Microsoft.AspNetCore.SignalR.Client.TS/HubConnection.ts
index 3dc7c481a1..7e9a03f739 100644
--- a/client-ts/Microsoft.AspNetCore.SignalR.Client.TS/HubConnection.ts
+++ b/client-ts/Microsoft.AspNetCore.SignalR.Client.TS/HubConnection.ts
@@ -21,6 +21,7 @@ export class HubConnection {
     private callbacks: Map<string, (invocationDescriptor: InvocationResultDescriptor) => void>;
     private methods: Map<string, (...args: any[]) => void>;
     private id: number;
+    private connectionClosedCallback: ConnectionClosed;
 
     static create(url: string, queryString?: string): HubConnection {
         return new this(new Connection(url, queryString))
@@ -33,6 +34,9 @@ export class HubConnection {
         this.connection.onDataReceived = data => {
             this.onDataReceived(data);
         };
+        this.connection.onClosed = (error: Error) => {
+            this.onConnectionClosed(error);
+        }
 
         this.callbacks = new Map<string, (invocationDescriptor: InvocationResultDescriptor) => void>();
         this.methods = new Map<string, (...args: any[]) => void>();
@@ -48,7 +52,7 @@ export class HubConnection {
         var descriptor = JSON.parse(data);
         if (descriptor.Method === undefined) {
             let invocationResult: InvocationResultDescriptor = descriptor;
-            let callback = this.callbacks[invocationResult.Id];
+            let callback = this.callbacks.get(invocationResult.Id);
             if (callback != null) {
                 callback(invocationResult);
                 this.callbacks.delete(invocationResult.Id);
@@ -64,6 +68,23 @@ export class HubConnection {
         }
     }
 
+    private onConnectionClosed(error: Error) {
+        let errorInvocationResult = {
+            Id: "-1",
+            Error: error ? error.message : "Invocation cancelled due to connection being closed.",
+            Result: null
+        } as InvocationResultDescriptor;
+
+        this.callbacks.forEach(callback => {
+            callback(errorInvocationResult);
+        });
+        this.callbacks.clear();
+
+        if (this.connectionClosedCallback) {
+            this.connectionClosedCallback(error);
+        }
+    }
+
     start(transportName? :string): Promise<void> {
         return this.connection.start(transportName);
     }
@@ -83,20 +104,20 @@ export class HubConnection {
         };
 
         let p = new Promise<any>((resolve, reject) => {
-            this.callbacks[id] = (invocationResult: InvocationResultDescriptor) => {
+            this.callbacks.set(invocationDescriptor.Id, (invocationResult: InvocationResultDescriptor) => {
                 if (invocationResult.Error != null) {
                     reject(new Error(invocationResult.Error));
                 }
                 else {
                     resolve(invocationResult.Result);
                 }
-            };
+            });
 
             //TODO: separate conversion to enable different data formats
             this.connection.send(JSON.stringify(invocationDescriptor))
                 .catch(e => {
-                    // TODO: remove callback
                     reject(e);
+                    this.callbacks.delete(invocationDescriptor.Id);
                 });
         });
 
@@ -108,6 +129,6 @@ export class HubConnection {
     }
 
     set onClosed(callback: ConnectionClosed) {
-        this.connection.onClosed = callback;
+        this.connectionClosedCallback = callback;
     }
 }