diff --git a/types/write-file-atomic/index.d.ts b/types/write-file-atomic/index.d.ts
index bcd5ede02c..8981acd483 100644
--- a/types/write-file-atomic/index.d.ts
+++ b/types/write-file-atomic/index.d.ts
@@ -2,25 +2,29 @@
 // Project: https://github.com/npm/write-file-atomic
 // Definitions by: BendingBender <https://github.com/BendingBender>
 //                 Jay Rylan <https://github.com/jayrylan>
+//                 Piotr Błażejewicz <https://github.com/peterblazejewicz>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
 
 /// <reference types="node" />
 
 export = writeFile;
 
-declare function writeFile(filename: string, data: string | Buffer, options: writeFile.Options, callback: (error?: Error) => void): void;
+declare function writeFile(filename: string, data: string | Buffer, options: writeFile.Options | BufferEncoding, callback: (error?: Error) => void): void;
 declare function writeFile(filename: string, data: string | Buffer, callback: (error?: Error) => void): void;
-declare function writeFile(filename: string, data: string | Buffer, options?: writeFile.Options): Promise<void>;
+declare function writeFile(filename: string, data: string | Buffer, options?: writeFile.Options | BufferEncoding): Promise<void>;
 
 declare namespace writeFile {
-    function sync(filename: string, data: string | Buffer, options?: Options): void;
+    function sync(filename: string, data: string | Buffer, options?: Options | BufferEncoding): void;
 
     interface Options {
         chown?: {
             uid: number;
             gid: number;
         };
-        encoding?: string;
+        /**
+         * @default 'utf8'
+         */
+        encoding?: BufferEncoding;
         fsync?: boolean;
         mode?: number;
     }
diff --git a/types/write-file-atomic/write-file-atomic-tests.ts b/types/write-file-atomic/write-file-atomic-tests.ts
index 4defd48f7b..28e08d871e 100644
--- a/types/write-file-atomic/write-file-atomic-tests.ts
+++ b/types/write-file-atomic/write-file-atomic-tests.ts
@@ -3,16 +3,17 @@ import writeFileAtomic = require('write-file-atomic');
 writeFileAtomic('message.txt', 'Hello Node', err => {});
 
 writeFileAtomic('message.txt', 'Hello Node', {chown: {uid: 100, gid: 50}}, err => {});
-writeFileAtomic('message.txt', 'Hello Node', {encoding: ''}, err => {});
 writeFileAtomic('message.txt', 'Hello Node', {fsync: false}, err => {});
 writeFileAtomic('message.txt', 'Hello Node', {mode: 123}, err => {});
+writeFileAtomic('message.txt', 'Hello Node', 'utf8', err => {});
 
 writeFileAtomic('message.txt', 'Hello Node').then(() => {}).catch(() => {});
 writeFileAtomic('message.txt', 'Hello Node', {mode: 123}).then(() => {}).catch(() => {});
+writeFileAtomic('message.txt', 'Hello Node', 'utf8').then(() => {}).catch(() => {});
 
 writeFileAtomic.sync('message.txt', 'Hello Node');
 
 writeFileAtomic.sync('message.txt', 'Hello Node', {chown: {uid: 100, gid: 50}});
-writeFileAtomic.sync('message.txt', 'Hello Node', {encoding: ''});
 writeFileAtomic.sync('message.txt', 'Hello Node', {fsync: false});
 writeFileAtomic.sync('message.txt', 'Hello Node', {mode: 123});
+writeFileAtomic.sync('message.txt', 'Hello Node', 'utf8');