diff --git a/docs/recipes/typescript.md b/docs/recipes/typescript.md
index 29a1a283f..b6b20e83e 100644
--- a/docs/recipes/typescript.md
+++ b/docs/recipes/typescript.md
@@ -66,7 +66,7 @@ import test, {Macro} from 'ava';
 const macro: Macro = (t, input: string, expected: number) => {
 	t.is(eval(input), expected);
 };
-macro.title = (providedTitle: string, input: string, expected: number) => `${providedTitle} ${input} = ${expected}`.trim();
+macro.title = (providedTitle = '', input: string, expected: number) => `${providedTitle} ${input} = ${expected}`.trim();
 
 test(macro, '2 + 2', 4);
 test(macro, '2 * 3', 6);
diff --git a/index.d.ts b/index.d.ts
index 97f2567a5..f6032f1e2 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -390,13 +390,13 @@ export interface Macro<Context = {}> {
 	 * Implement this function to generate a test (or hook) title whenever this macro is used. `providedTitle` contains
 	 * the title provided when the test or hook was declared. Also receives the remaining test arguments.
 	 */
-	title?: (providedTitle: string, ...args: Array<any>) => string;
+	title?: (providedTitle: string | undefined, ...args: Array<any>) => string;
 }
 
 /** A reusable test or hook implementation, for tests & hooks declared with the `.cb` modifier. */
 export interface CbMacro<Context = {}> {
 	(t: CbExecutionContext<Context>, ...args: Array<any>): ImplementationResult;
-	title?: (providedTitle: string, ...args: Array<any>) => string;
+	title?: (providedTitle: string | undefined, ...args: Array<any>) => string;
 }
 
 export interface TestInterface<Context = {}> {
diff --git a/index.js.flow b/index.js.flow
index 479e5d022..22f0eaadf 100644
--- a/index.js.flow
+++ b/index.js.flow
@@ -403,13 +403,13 @@ export interface Macro<Context = {}> {
 	 * Implement this function to generate a test (or hook) title whenever this macro is used. `providedTitle` contains
 	 * the title provided when the test or hook was declared. Also receives the remaining test arguments.
 	 */
-	title?: (providedTitle: string, ...args: Array<any>) => string;
+	title?: (providedTitle: string | void, ...args: Array<any>) => string;
 }
 
 /** A reusable test or hook implementation, for tests & hooks declared with the `.cb` modifier. */
 export interface CbMacro<Context = {}> {
 	(t: CbExecutionContext<Context>, ...args: Array<any>): ImplementationResult;
-	title?: (providedTitle: string, ...args: Array<any>) => string;
+	title?: (providedTitle: string | void, ...args: Array<any>) => string;
 }
 
 export interface TestInterface<Context = {}> {
diff --git a/lib/runner.js b/lib/runner.js
index 67486b04f..73bbc1b50 100644
--- a/lib/runner.js
+++ b/lib/runner.js
@@ -55,7 +55,7 @@ class Runner extends Emittery {
 
 			const specifiedTitle = typeof args[0] === 'string' ?
 				args.shift() :
-				'';
+				undefined;
 			const implementations = Array.isArray(args[0]) ?
 				args.shift() :
 				args.splice(0, 1);
@@ -65,7 +65,7 @@ class Runner extends Emittery {
 					throw new TypeError('`todo` tests are not allowed to have an implementation. Use `test.skip()` for tests with an implementation.');
 				}
 
-				if (specifiedTitle === '') {
+				if (specifiedTitle === undefined || specifiedTitle === '') {
 					throw new TypeError('`todo` tests require a title');
 				}
 
@@ -97,14 +97,14 @@ class Runner extends Emittery {
 
 				for (const implementation of implementations) {
 					let title = implementation.title ?
-						implementation.title.apply(implementation, [specifiedTitle].concat(args)) :
+						implementation.title(specifiedTitle, ...args) :
 						specifiedTitle;
 
-					if (typeof title !== 'string') {
+					if (title !== undefined && typeof title !== 'string') {
 						throw new TypeError('Test & hook titles must be strings');
 					}
 
-					if (title === '') {
+					if (title === undefined || title === '') {
 						if (metadata.type === 'test') {
 							throw new TypeError('Tests must have a title');
 						} else if (metadata.always) {
diff --git a/readme.md b/readme.md
index d7eaa48e3..84ec6dc01 100644
--- a/readme.md
+++ b/readme.md
@@ -691,14 +691,14 @@ function macro(t, input, expected) {
 	t.is(eval(input), expected);
 }
 
-macro.title = (providedTitle, input, expected) => `${providedTitle} ${input} = ${expected}`.trim();
+macro.title = (providedTitle = '', input, expected) => `${providedTitle} ${input} = ${expected}`.trim();
 
 test(macro, '2 + 2', 4);
 test(macro, '2 * 3', 6);
 test('providedTitle', macro, '3 * 3', 9);
 ```
 
-The `providedTitle` argument defaults to an empty string if the user does not supply a string title. This allows for easy concatenation without having to worry about `null` / `undefined`. It is worth remembering that the empty string is considered a falsy value, so you can still use `if(providedTitle) {...}`.
+The `providedTitle` argument defaults to `undefined` if the user does not supply a string title. This means you can use a parameter assignment to set the default value. The example above uses the empty string as the default.
 
 You can also pass arrays of macro functions:
 
diff --git a/test/runner.js b/test/runner.js
index 6ec4e4b3a..1fbed8e8d 100644
--- a/test/runner.js
+++ b/test/runner.js
@@ -611,7 +611,7 @@ test('macros: Customize test names attaching a `title` function', t => {
 		avaT.pass();
 	}
 
-	macroFn.title = (title, firstArg) => (title || 'default') + firstArg;
+	macroFn.title = (title = 'default', firstArg) => title + firstArg;
 
 	return promiseEnd(new Runner(), runner => {
 		runner.on('stateChange', evt => {