diff --git a/types/node/index.d.ts b/types/node/index.d.ts
index 7551a5190b..db864d60c2 100644
--- a/types/node/index.d.ts
+++ b/types/node/index.d.ts
@@ -4013,7 +4013,8 @@ declare module "assert" {
             });
         }
 
-        export function fail(actual: any, expected: any, message: string, operator: string): void;
+        export function fail(message: string): void;
+        export function fail(actual: any, expected: any, message?: string, operator?: string): void;
         export function ok(value: any, message?: string): void;
         export function equal(actual: any, expected: any, message?: string): void;
         export function notEqual(actual: any, expected: any, message?: string): void;
diff --git a/types/node/node-tests.ts b/types/node/node-tests.ts
index fef0cd9862..6530ccd381 100644
--- a/types/node/node-tests.ts
+++ b/types/node/node-tests.ts
@@ -63,6 +63,10 @@ namespace assert_tests {
 
         assert.equal(3, "3", "uses == comparator");
 
+        assert.fail('stuff broke');
+
+        assert.fail('actual', 'expected', 'message');
+
         assert.fail(1, 2, undefined, '>');
 
         assert.ifError(0);
diff --git a/types/node/v4/index.d.ts b/types/node/v4/index.d.ts
index a79f49e35d..84e531f004 100644
--- a/types/node/v4/index.d.ts
+++ b/types/node/v4/index.d.ts
@@ -2281,7 +2281,7 @@ declare module "assert" {
                                   operator?: string; stackStartFunction?: Function});
         }
 
-        export function fail(actual?: any, expected?: any, message?: string, operator?: string): void;
+        export function fail(actual: any, expected: any, message?: string, operator?: string): void;
         export function ok(value: any, message?: string): void;
         export function equal(actual: any, expected: any, message?: string): void;
         export function notEqual(actual: any, expected: any, message?: string): void;
diff --git a/types/node/v6/index.d.ts b/types/node/v6/index.d.ts
index 0b87d6f2f6..9732f6bf2b 100644
--- a/types/node/v6/index.d.ts
+++ b/types/node/v6/index.d.ts
@@ -3693,7 +3693,7 @@ declare module "assert" {
             });
         }
 
-        export function fail(actual: any, expected: any, message: string, operator: string): void;
+        export function fail(actual: any, expected: any, message?: string, operator?: string): void;
         export function ok(value: any, message?: string): void;
         export function equal(actual: any, expected: any, message?: string): void;
         export function notEqual(actual: any, expected: any, message?: string): void;
diff --git a/types/node/v6/node-tests.ts b/types/node/v6/node-tests.ts
index 191f1128c2..b1aee63753 100644
--- a/types/node/v6/node-tests.ts
+++ b/types/node/v6/node-tests.ts
@@ -61,6 +61,8 @@ namespace assert_tests {
 
         assert.equal(3, "3", "uses == comparator");
 
+        assert.fail("actual", "expected", "message");
+
         assert.fail(1, 2, undefined, '>');
 
         assert.ifError(0);
diff --git a/types/node/v7/index.d.ts b/types/node/v7/index.d.ts
index 59b3d680c7..0e9c7288f0 100644
--- a/types/node/v7/index.d.ts
+++ b/types/node/v7/index.d.ts
@@ -3844,7 +3844,7 @@ declare module "assert" {
             });
         }
 
-        export function fail(actual: any, expected: any, message: string, operator: string): void;
+        export function fail(actual: any, expected: any, message?: string, operator?: string): void;
         export function ok(value: any, message?: string): void;
         export function equal(actual: any, expected: any, message?: string): void;
         export function notEqual(actual: any, expected: any, message?: string): void;
diff --git a/types/node/v7/node-tests.ts b/types/node/v7/node-tests.ts
index 4a2f53ab67..0fad40256a 100644
--- a/types/node/v7/node-tests.ts
+++ b/types/node/v7/node-tests.ts
@@ -62,6 +62,8 @@ namespace assert_tests {
 
         assert.equal(3, "3", "uses == comparator");
 
+        assert.fail("actual", "expected", "message");
+
         assert.fail(1, 2, undefined, '>');
 
         assert.ifError(0);