diff --git a/types/node/index.d.ts b/types/node/index.d.ts
index 2e31fff6e6..3404e37d46 100644
--- a/types/node/index.d.ts
+++ b/types/node/index.d.ts
@@ -5615,8 +5615,8 @@ declare module "assert" {
             });
         }
 
-        export function fail(message: string): void;
-        export function fail(actual: any, expected: any, message?: string, operator?: string): void;
+        export function fail(message: string): never;
+        export function fail(actual: any, expected: any, message?: string, operator?: string): never;
         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/v0/index.d.ts b/types/node/v0/index.d.ts
index 800a909c49..ef1c485d2d 100644
--- a/types/node/v0/index.d.ts
+++ b/types/node/v0/index.d.ts
@@ -1870,7 +1870,7 @@ 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): never;
         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/v4/index.d.ts b/types/node/v4/index.d.ts
index 16e54d002d..ada62b683e 100644
--- a/types/node/v4/index.d.ts
+++ b/types/node/v4/index.d.ts
@@ -2448,7 +2448,7 @@ 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): never;
         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 3ca66a2df5..f38cdf01dd 100644
--- a/types/node/v6/index.d.ts
+++ b/types/node/v6/index.d.ts
@@ -3876,7 +3876,7 @@ 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): never;
         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/index.d.ts b/types/node/v7/index.d.ts
index 62e30f0f09..896b5a887f 100644
--- a/types/node/v7/index.d.ts
+++ b/types/node/v7/index.d.ts
@@ -3984,7 +3984,7 @@ 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): never;
         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/v8/index.d.ts b/types/node/v8/index.d.ts
index fd1f5cafae..4bd4977d5f 100644
--- a/types/node/v8/index.d.ts
+++ b/types/node/v8/index.d.ts
@@ -5585,8 +5585,8 @@ declare module "assert" {
             });
         }
 
-        export function fail(message: string): void;
-        export function fail(actual: any, expected: any, message?: string, operator?: string): void;
+        export function fail(message: string): never;
+        export function fail(actual: any, expected: any, message?: string, operator?: string): never;
         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;