diff --git a/src/vs/platform/extensionManagement/common/extensionGalleryService.ts b/src/vs/platform/extensionManagement/common/extensionGalleryService.ts
index 4466945eb97..5f9eb66ab94 100644
--- a/src/vs/platform/extensionManagement/common/extensionGalleryService.ts
+++ b/src/vs/platform/extensionManagement/common/extensionGalleryService.ts
@@ -11,6 +11,7 @@ import { IPager } from 'vs/base/common/paging';
 import { isWeb } from 'vs/base/common/platform';
 import { URI } from 'vs/base/common/uri';
 import { IHeaders, IRequestContext, IRequestOptions } from 'vs/base/parts/request/common/request';
+import { IConfigurationService } from 'vs/platform/configuration/common/configuration';
 import { IEnvironmentService } from 'vs/platform/environment/common/environment';
 import { CURRENT_TARGET_PLATFORM, DefaultIconPath, IExtensionGalleryService, IExtensionIdentifier, IExtensionIdentifierWithVersion, IGalleryExtension, IGalleryExtensionAsset, IGalleryExtensionAssets, IGalleryExtensionVersion, InstallOperation, IQueryOptions, IReportedExtension, isIExtensionIdentifier, ITranslation, SortBy, SortOrder, StatisticType, TargetPlatform, toTargetPlatform, WEB_EXTENSION_TAG } from 'vs/platform/extensionManagement/common/extensionManagement';
 import { adoptToGalleryExtensionId, areSameExtensions, getGalleryExtensionId, getGalleryExtensionTelemetryData } from 'vs/platform/extensionManagement/common/extensionManagementUtil';
@@ -24,6 +25,7 @@ import { asJson, asText, IRequestService, isSuccess } from 'vs/platform/request/
 import { getServiceMachineId } from 'vs/platform/serviceMachineId/common/serviceMachineId';
 import { IStorageService, StorageScope, StorageTarget } from 'vs/platform/storage/common/storage';
 import { ITelemetryService } from 'vs/platform/telemetry/common/telemetry';
+import { getTelemetryLevel, TelemetryLevel } from 'vs/platform/telemetry/common/telemetryUtils';
 
 interface IRawGalleryExtensionFile {
 	readonly assetType: string;
@@ -460,12 +462,13 @@ export class ExtensionGalleryService implements IExtensionGalleryService {
 		@ITelemetryService private readonly telemetryService: ITelemetryService,
 		@IFileService private readonly fileService: IFileService,
 		@IProductService private readonly productService: IProductService,
+		@IConfigurationService private readonly configurationService: IConfigurationService,
 		@optional(IStorageService) storageService: IStorageService,
 	) {
 		const config = productService.extensionsGallery;
 		this.extensionsGalleryUrl = config && config.serviceUrl;
 		this.extensionsControlUrl = config && config.controlUrl;
-		this.commonHeadersPromise = resolveMarketplaceHeaders(productService.version, this.environmentService, this.fileService, storageService);
+		this.commonHeadersPromise = resolveMarketplaceHeaders(productService.version, productService, this.environmentService, this.configurationService, this.fileService, storageService);
 	}
 
 	private api(path = ''): string {
@@ -927,7 +930,7 @@ export class ExtensionGalleryService implements IExtensionGalleryService {
 	}
 }
 
-export async function resolveMarketplaceHeaders(version: string, environmentService: IEnvironmentService, fileService: IFileService, storageService: {
+export async function resolveMarketplaceHeaders(version: string, productService: IProductService, environmentService: IEnvironmentService, configurationService: IConfigurationService, fileService: IFileService, storageService: {
 	get: (key: string, scope: StorageScope) => string | undefined,
 	store: (key: string, value: string, scope: StorageScope, target: StorageTarget) => void
 } | undefined): Promise<{ [key: string]: string; }> {
@@ -936,6 +939,8 @@ export async function resolveMarketplaceHeaders(version: string, environmentServ
 		'User-Agent': `VSCode ${version}`
 	};
 	const uuid = await getServiceMachineId(environmentService, fileService, storageService);
-	headers['X-Market-User-Id'] = uuid;
+	if (getTelemetryLevel(productService, environmentService) === TelemetryLevel.USER && configurationService.getValue('telemetry.enableTelemetry') === true) {
+		headers['X-Market-User-Id'] = uuid;
+	}
 	return headers;
 }
diff --git a/src/vs/platform/extensionManagement/test/common/extensionGalleryService.test.ts b/src/vs/platform/extensionManagement/test/common/extensionGalleryService.test.ts
index 603165c8719..1c3d759990b 100644
--- a/src/vs/platform/extensionManagement/test/common/extensionGalleryService.test.ts
+++ b/src/vs/platform/extensionManagement/test/common/extensionGalleryService.test.ts
@@ -9,6 +9,8 @@ import { joinPath } from 'vs/base/common/resources';
 import { URI } from 'vs/base/common/uri';
 import { isUUID } from 'vs/base/common/uuid';
 import { mock } from 'vs/base/test/common/mock';
+import { IConfigurationService } from 'vs/platform/configuration/common/configuration';
+import { TestConfigurationService } from 'vs/platform/configuration/test/common/testConfigurationService';
 import { IEnvironmentService } from 'vs/platform/environment/common/environment';
 import { resolveMarketplaceHeaders } from 'vs/platform/extensionManagement/common/extensionGalleryService';
 import { IFileService } from 'vs/platform/files/common/files';
@@ -16,6 +18,7 @@ import { FileService } from 'vs/platform/files/common/fileService';
 import { InMemoryFileSystemProvider } from 'vs/platform/files/common/inMemoryFilesystemProvider';
 import { NullLogService } from 'vs/platform/log/common/log';
 import product from 'vs/platform/product/common/product';
+import { IProductService } from 'vs/platform/product/common/productService';
 import { InMemoryStorageService, IStorageService } from 'vs/platform/storage/common/storage';
 
 class EnvironmentServiceMock extends mock<IEnvironmentService>() {
@@ -28,7 +31,7 @@ class EnvironmentServiceMock extends mock<IEnvironmentService>() {
 
 suite('Extension Gallery Service', () => {
 	const disposables: DisposableStore = new DisposableStore();
-	let fileService: IFileService, environmentService: IEnvironmentService, storageService: IStorageService;
+	let fileService: IFileService, environmentService: IEnvironmentService, storageService: IStorageService, productService: IProductService, configurationService: IConfigurationService;
 
 	setup(() => {
 		const serviceMachineIdResource = joinPath(URI.file('tests').with({ scheme: 'vscode-tests' }), 'machineid');
@@ -37,14 +40,16 @@ suite('Extension Gallery Service', () => {
 		const fileSystemProvider = disposables.add(new InMemoryFileSystemProvider());
 		fileService.registerProvider(serviceMachineIdResource.scheme, fileSystemProvider);
 		storageService = new InMemoryStorageService();
+		configurationService = new TestConfigurationService();
+		productService = { _serviceBrand: undefined, ...product };
 	});
 
 	teardown(() => disposables.clear());
 
 	test('marketplace machine id', async () => {
-		const headers = await resolveMarketplaceHeaders(product.version, environmentService, fileService, storageService);
+		const headers = await resolveMarketplaceHeaders(product.version, productService, environmentService, configurationService, fileService, storageService);
 		assert.ok(isUUID(headers['X-Market-User-Id']));
-		const headers2 = await resolveMarketplaceHeaders(product.version, environmentService, fileService, storageService);
+		const headers2 = await resolveMarketplaceHeaders(product.version, productService, environmentService, configurationService, fileService, storageService);
 		assert.strictEqual(headers['X-Market-User-Id'], headers2['X-Market-User-Id']);
 	});
 });
diff --git a/src/vs/platform/userDataSync/common/userDataSyncStoreService.ts b/src/vs/platform/userDataSync/common/userDataSyncStoreService.ts
index 13ac211dfd1..8046bf6c331 100644
--- a/src/vs/platform/userDataSync/common/userDataSyncStoreService.ts
+++ b/src/vs/platform/userDataSync/common/userDataSyncStoreService.ts
@@ -175,7 +175,6 @@ export class UserDataSyncStoreClient extends Disposable implements IUserDataSync
 				const headers: IHeaders = {
 					'X-Client-Name': `${productService.applicationName}${isWeb ? '-web' : ''}`,
 					'X-Client-Version': productService.version,
-					'X-Machine-Id': uuid
 				};
 				if (productService.commit) {
 					headers['X-Client-Commit'] = productService.commit;
diff --git a/src/vs/platform/userDataSync/test/common/userDataSyncStoreService.test.ts b/src/vs/platform/userDataSync/test/common/userDataSyncStoreService.test.ts
index 4bd5b838ff7..4fd656fa644 100644
--- a/src/vs/platform/userDataSync/test/common/userDataSyncStoreService.test.ts
+++ b/src/vs/platform/userDataSync/test/common/userDataSyncStoreService.test.ts
@@ -88,7 +88,6 @@ suite('UserDataSyncStoreService', () => {
 		assert.strictEqual(target.requestsWithAllHeaders.length, 1);
 		assert.strictEqual(target.requestsWithAllHeaders[0].headers!['X-Client-Name'], `${productService.applicationName}${isWeb ? '-web' : ''}`);
 		assert.strictEqual(target.requestsWithAllHeaders[0].headers!['X-Client-Version'], productService.version);
-		assert.notStrictEqual(target.requestsWithAllHeaders[0].headers!['X-Machine-Id'], undefined);
 		assert.notStrictEqual(target.requestsWithAllHeaders[0].headers!['X-Machine-Session-Id'], undefined);
 		assert.strictEqual(target.requestsWithAllHeaders[0].headers!['X-User-Session-Id'], undefined);
 	});
diff --git a/src/vs/platform/windows/electron-main/window.ts b/src/vs/platform/windows/electron-main/window.ts
index 8e3e960e028..7483dee08ab 100644
--- a/src/vs/platform/windows/electron-main/window.ts
+++ b/src/vs/platform/windows/electron-main/window.ts
@@ -302,7 +302,7 @@ export class CodeWindow extends Disposable implements ICodeWindow {
 		this.createTouchBar();
 
 		// Request handling
-		this.marketplaceHeadersPromise = resolveMarketplaceHeaders(this.productService.version, this.environmentMainService, this.fileService, {
+		this.marketplaceHeadersPromise = resolveMarketplaceHeaders(this.productService.version, this.productService, this.environmentMainService, this.configurationService, this.fileService, {
 			get: key => storageMainService.globalStorage.get(key),
 			store: (key, value) => storageMainService.globalStorage.set(key, value)
 		});
diff --git a/src/vs/workbench/services/extensionResourceLoader/browser/extensionResourceLoaderService.ts b/src/vs/workbench/services/extensionResourceLoader/browser/extensionResourceLoaderService.ts
index 0178c4a175f..06a61593eca 100644
--- a/src/vs/workbench/services/extensionResourceLoader/browser/extensionResourceLoaderService.ts
+++ b/src/vs/workbench/services/extensionResourceLoader/browser/extensionResourceLoaderService.ts
@@ -14,6 +14,8 @@ import { getServiceMachineId } from 'vs/platform/serviceMachineId/common/service
 import { IEnvironmentService } from 'vs/platform/environment/common/environment';
 import { isWeb } from 'vs/base/common/platform';
 import { ILogService } from 'vs/platform/log/common/log';
+import { getTelemetryLevel, TelemetryLevel } from 'vs/platform/telemetry/common/telemetryUtils';
+import { IConfigurationService } from 'vs/platform/configuration/common/configuration';
 
 class ExtensionResourceLoaderService implements IExtensionResourceLoaderService {
 
@@ -27,6 +29,7 @@ class ExtensionResourceLoaderService implements IExtensionResourceLoaderService
 		@IStorageService private readonly _storageService: IStorageService,
 		@IEnvironmentService private readonly _environmentService: IEnvironmentService,
 		@ILogService private readonly _logService: ILogService,
+		@IConfigurationService private readonly _configurationService: IConfigurationService
 	) {
 		if (_productService.extensionsGallery) {
 			this._extensionGalleryResourceAuthority = this._getExtensionResourceAuthority(URI.parse(_productService.extensionsGallery.resourceUrlTemplate));
@@ -46,9 +49,11 @@ class ExtensionResourceLoaderService implements IExtensionResourceLoaderService
 			const machineId = await this._getServiceMachineId();
 			requestInit.headers = {
 				'X-Client-Name': `${this._productService.applicationName}${isWeb ? '-web' : ''}`,
-				'X-Client-Version': this._productService.version,
-				'X-Machine-Id': machineId
+				'X-Client-Version': this._productService.version
 			};
+			if (getTelemetryLevel(this._productService, this._environmentService) === TelemetryLevel.USER && this._configurationService.getValue('telemetry.enableTelemetry') === true) {
+				requestInit.headers['X-Machine-Id'] = machineId;
+			}
 			if (this._productService.commit) {
 				requestInit.headers['X-Client-Commit'] = this._productService.commit;
 			}