diff --git a/src/vs/vscode.proposed.d.ts b/src/vs/vscode.proposed.d.ts
index 0a2309b566877..939d77562e3a8 100644
--- a/src/vs/vscode.proposed.d.ts
+++ b/src/vs/vscode.proposed.d.ts
@@ -147,6 +147,11 @@ declare module 'vscode' {
 		 * Note that these are of type TunnelDescription and cannot be disposed.
 		 */
 		export let tunnels: Thenable<TunnelDescription[]>;
+
+		/**
+		 * Fired when the list of tunnels has changed.
+		 */
+		export const onDidTunnelsChange: Event<void>;
 	}
 
 	export interface ResourceLabelFormatter {
diff --git a/src/vs/workbench/api/browser/mainThreadTunnelService.ts b/src/vs/workbench/api/browser/mainThreadTunnelService.ts
index 57718a1cbbb9f..cc55545aea2ab 100644
--- a/src/vs/workbench/api/browser/mainThreadTunnelService.ts
+++ b/src/vs/workbench/api/browser/mainThreadTunnelService.ts
@@ -22,6 +22,8 @@ export class MainThreadTunnelService extends Disposable implements MainThreadTun
 	) {
 		super();
 		this._proxy = extHostContext.getProxy(ExtHostContext.ExtHostTunnelService);
+		this._register(tunnelService.onTunnelOpened(() => this._proxy.$onDidTunnelsChange()));
+		this._register(tunnelService.onTunnelClosed(() => this._proxy.$onDidTunnelsChange()));
 	}
 
 	async $openTunnel(tunnelOptions: TunnelOptions): Promise<TunnelDto | undefined> {
diff --git a/src/vs/workbench/api/common/extHost.api.impl.ts b/src/vs/workbench/api/common/extHost.api.impl.ts
index fa2f702323b39..76aa93aab1ce2 100644
--- a/src/vs/workbench/api/common/extHost.api.impl.ts
+++ b/src/vs/workbench/api/common/extHost.api.impl.ts
@@ -765,6 +765,9 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 			},
 			get tunnels() {
 				return extHostTunnelService.getTunnels();
+			},
+			onDidTunnelsChange: (listener, thisArg?, disposables?) => {
+				return extHostTunnelService.onDidTunnelsChange(listener, thisArg, disposables);
 			}
 		};
 
diff --git a/src/vs/workbench/api/common/extHost.protocol.ts b/src/vs/workbench/api/common/extHost.protocol.ts
index 7c62fad573d32..ff5a245e7ed89 100644
--- a/src/vs/workbench/api/common/extHost.protocol.ts
+++ b/src/vs/workbench/api/common/extHost.protocol.ts
@@ -1423,6 +1423,7 @@ export interface ExtHostTunnelServiceShape {
 	$filterCandidates(candidates: { host: string, port: number, detail: string }[]): Promise<boolean[]>;
 	$forwardPort(tunnelOptions: TunnelOptions): Promise<TunnelDto> | undefined;
 	$closeTunnel(remote: { host: string, port: number }): Promise<void>;
+	$onDidTunnelsChange(): Promise<void>;
 }
 
 // --- proxy identifiers
diff --git a/src/vs/workbench/api/common/extHostTunnelService.ts b/src/vs/workbench/api/common/extHostTunnelService.ts
index d92b8be4daf58..6e5e59dd044c0 100644
--- a/src/vs/workbench/api/common/extHostTunnelService.ts
+++ b/src/vs/workbench/api/common/extHostTunnelService.ts
@@ -8,6 +8,7 @@ import { createDecorator } from 'vs/platform/instantiation/common/instantiation'
 import type * as vscode from 'vscode';
 import { RemoteTunnel, TunnelOptions } from 'vs/platform/remote/common/tunnel';
 import { IDisposable } from 'vs/base/common/lifecycle';
+import { Emitter } from 'vs/base/common/event';
 
 export interface TunnelDto {
 	remoteAddress: { port: number, host: string };
@@ -32,6 +33,7 @@ export interface IExtHostTunnelService extends ExtHostTunnelServiceShape {
 	readonly _serviceBrand: undefined;
 	openTunnel(forward: TunnelOptions): Promise<vscode.Tunnel | undefined>;
 	getTunnels(): Promise<vscode.TunnelDescription[]>;
+	onDidTunnelsChange: vscode.Event<void>;
 	setTunnelExtensionFunctions(provider: vscode.RemoteAuthorityResolver | undefined): Promise<IDisposable>;
 }
 
@@ -39,6 +41,8 @@ export const IExtHostTunnelService = createDecorator<IExtHostTunnelService>('IEx
 
 export class ExtHostTunnelService implements IExtHostTunnelService {
 	_serviceBrand: undefined;
+	onDidTunnelsChange: vscode.Event<void> = (new Emitter<void>()).event;
+
 	async openTunnel(forward: TunnelOptions): Promise<vscode.Tunnel | undefined> {
 		return undefined;
 	}
@@ -54,5 +58,5 @@ export class ExtHostTunnelService implements IExtHostTunnelService {
 	async setTunnelExtensionFunctions(provider: vscode.RemoteAuthorityResolver | undefined): Promise<IDisposable> { return { dispose: () => { } }; }
 	$forwardPort(tunnelOptions: TunnelOptions): Promise<TunnelDto> | undefined { return undefined; }
 	async $closeTunnel(remote: { host: string, port: number }): Promise<void> { }
-
+	async $onDidTunnelsChange(): Promise<void> { }
 }
diff --git a/src/vs/workbench/api/node/extHostTunnelService.ts b/src/vs/workbench/api/node/extHostTunnelService.ts
index 9af73f1b77008..8930d91e856e0 100644
--- a/src/vs/workbench/api/node/extHostTunnelService.ts
+++ b/src/vs/workbench/api/node/extHostTunnelService.ts
@@ -39,6 +39,8 @@ export class ExtHostTunnelService extends Disposable implements IExtHostTunnelSe
 	private _forwardPortProvider: ((tunnelOptions: TunnelOptions) => Thenable<vscode.Tunnel> | undefined) | undefined;
 	private _showCandidatePort: (host: string, port: number, detail: string) => Thenable<boolean> = () => { return Promise.resolve(true); };
 	private _extensionTunnels: Map<string, Map<number, vscode.Tunnel>> = new Map();
+	private _onDidTunnelsChange: Emitter<void> = new Emitter<void>();
+	onDidTunnelsChange: vscode.Event<void> = this._onDidTunnelsChange.event;
 
 	constructor(
 		@IExtHostRpcService extHostRpc: IExtHostRpcService,
@@ -104,6 +106,10 @@ export class ExtHostTunnelService extends Disposable implements IExtHostTunnelSe
 		}
 	}
 
+	async $onDidTunnelsChange(): Promise<void> {
+		this._onDidTunnelsChange.fire();
+	}
+
 	$forwardPort(tunnelOptions: TunnelOptions): Promise<TunnelDto> | undefined {
 		if (this._forwardPortProvider) {
 			const providedPort = this._forwardPortProvider!(tunnelOptions);