diff --git a/src/vs/base/common/json.ts b/src/vs/base/common/json.ts
index 300eae4eb7e..98a6a6f68c9 100644
--- a/src/vs/base/common/json.ts
+++ b/src/vs/base/common/json.ts
@@ -629,7 +629,7 @@ export type JSONPath = Segment[];
 
 export interface ParseOptions {
 	disallowComments?: boolean;
-	allowTrailingComma?: boolean;
+	disallowTrailingComma?: boolean;
 }
 
 /**
@@ -818,7 +818,7 @@ export function visit(text: string, visitor: JSONVisitor, options?: ParseOptions
 		onError = toOneArgVisit(visitor.onError);
 
 	let disallowComments = options && options.disallowComments;
-	let allowTrailingComma = options && options.allowTrailingComma;
+	let disallowTrailingComma = options && options.disallowTrailingComma;
 	function scanNext(): SyntaxKind {
 		while (true) {
 			let token = _scanner.scan();
@@ -930,7 +930,7 @@ export function visit(text: string, visitor: JSONVisitor, options?: ParseOptions
 				}
 				onSeparator(',');
 				scanNext(); // consume comma
-				if (_scanner.getToken() === SyntaxKind.CloseBraceToken && allowTrailingComma) {
+				if (_scanner.getToken() === SyntaxKind.CloseBraceToken && !disallowTrailingComma) {
 					break;
 				}
 			} else if (needsComma) {
@@ -962,7 +962,7 @@ export function visit(text: string, visitor: JSONVisitor, options?: ParseOptions
 				}
 				onSeparator(',');
 				scanNext(); // consume comma
-				if (_scanner.getToken() === SyntaxKind.CloseBracketToken && allowTrailingComma) {
+				if (_scanner.getToken() === SyntaxKind.CloseBracketToken && !disallowTrailingComma) {
 					break;
 				}
 			} else if (needsComma) {
diff --git a/src/vs/base/test/common/json.test.ts b/src/vs/base/test/common/json.test.ts
index 2551f00fde3..3606713aa3b 100644
--- a/src/vs/base/test/common/json.test.ts
+++ b/src/vs/base/test/common/json.test.ts
@@ -229,15 +229,19 @@ suite('JSON', () => {
 	});
 
 	test('parse: trailing comma', () => {
-		let options = { allowTrailingComma: true };
+		// default is allow
+		assertValidParse('{ "hello": [], }', { hello: [] });
+
+		let options = { disallowTrailingComma: false };
 		assertValidParse('{ "hello": [], }', { hello: [] }, options);
 		assertValidParse('{ "hello": [] }', { hello: [] }, options);
 		assertValidParse('{ "hello": [], "world": {}, }', { hello: [], world: {} }, options);
 		assertValidParse('{ "hello": [], "world": {} }', { hello: [], world: {} }, options);
 		assertValidParse('{ "hello": [1,] }', { hello: [1] }, options);
 
-		assertInvalidParse('{ "hello": [], }', { hello: [] });
-		assertInvalidParse('{ "hello": [], "world": {}, }', { hello: [], world: {} });
+		options = { disallowTrailingComma: true };
+		assertInvalidParse('{ "hello": [], }', { hello: [] }, options);
+		assertInvalidParse('{ "hello": [], "world": {}, }', { hello: [], world: {} }, options);
 	});
 
 	test('tree: literals', () => {
diff --git a/src/vs/workbench/services/configuration/node/configurationEditingService.ts b/src/vs/workbench/services/configuration/node/configurationEditingService.ts
index ffea6529bbf..cc274bdbdb2 100644
--- a/src/vs/workbench/services/configuration/node/configurationEditingService.ts
+++ b/src/vs/workbench/services/configuration/node/configurationEditingService.ts
@@ -371,7 +371,7 @@ export class ConfigurationEditingService {
 			return false;
 		}
 		const parseErrors: json.ParseError[] = [];
-		json.parse(model.getValue(), parseErrors, { allowTrailingComma: true });
+		json.parse(model.getValue(), parseErrors);
 		return parseErrors.length > 0;
 	}
 
diff --git a/src/vs/workbench/services/configuration/node/jsonEditingService.ts b/src/vs/workbench/services/configuration/node/jsonEditingService.ts
index 2c47d99e7c6..13f2fe32f22 100644
--- a/src/vs/workbench/services/configuration/node/jsonEditingService.ts
+++ b/src/vs/workbench/services/configuration/node/jsonEditingService.ts
@@ -95,7 +95,7 @@ export class JSONEditingService implements IJSONEditingService {
 
 	private hasParseErrors(model: ITextModel): boolean {
 		const parseErrors: json.ParseError[] = [];
-		json.parse(model.getValue(), parseErrors, { allowTrailingComma: true });
+		json.parse(model.getValue(), parseErrors);
 		return parseErrors.length > 0;
 	}
 
diff --git a/src/vs/workbench/services/keybinding/common/keybindingEditing.ts b/src/vs/workbench/services/keybinding/common/keybindingEditing.ts
index 98b80945993..49bfd52bada 100644
--- a/src/vs/workbench/services/keybinding/common/keybindingEditing.ts
+++ b/src/vs/workbench/services/keybinding/common/keybindingEditing.ts
@@ -255,7 +255,7 @@ export class KeybindingsEditingService extends Disposable implements IKeybinding
 
 	private parse(model: ITextModel): { result: IUserFriendlyKeybinding[], parseErrors: json.ParseError[] } {
 		const parseErrors: json.ParseError[] = [];
-		const result = json.parse(model.getValue(), parseErrors, { allowTrailingComma: true });
+		const result = json.parse(model.getValue(), parseErrors);
 		return { result, parseErrors };
 	}