Expected 1 arguments, but got 0. ts(2554) — how to fix

error TS2554: Expected 1 arguments, but got 0.
error TS2554: Expected 2 arguments, but got 3.
error TS2555: Expected at least 1 arguments, but got 0.

Quick fix: Hover the function to see its signature and match it. Make a parameter optional with ? (function f(a?: string)) or give it a default (a = ''). For React useRef/useState in React 19 types, pass an initial value: useRef<HTMLDivElement>(null). For overloaded library functions, update @types/* to match the library version.

What it means

Unlike JavaScript, TypeScript checks the argument count. A parameter is required unless it is marked optional (?), has a default value, or is a rest parameter (...args). TS2554 lists how many it expected and how many you passed; TS2555 is the same for functions with a rest or optional tail ("at least N").

function greet(name: string) { return `hi ${name}`; }
greet();             // TS2554: Expected 1 arguments, but got 0.
greet("a", "b");     // TS2554: Expected 1 arguments, but got 2.

Fix 1: pass the expected arguments

Hover the function in your editor (or Ctrl+click to the definition) to see its signature, then match it. Often an argument was added to a function you own and not every call site was updated; tsc --noEmit lists them all.

Fix 2: make parameters optional

If the argument really can be left out, say so in the signature:

function greet(name?: string) {
  return `hi ${name ?? "there"}`;
}

function paginate(page = 1, size = 20) { /* ... */ }

function log(...parts: unknown[]) { console.log(...parts); }

For many optional settings use an options object: function connect(opts: { host?: string; port?: number } = {}).

Fix 3: new Promise resolve with no value

await new Promise((resolve) => setTimeout(() => resolve(), 100));
// TS2554: Expected 1 arguments, but got 0.  (Did you forget to include 'void' in your type argument to 'Promise'?)

Fix: declare the promise as Promise<void>:

await new Promise<void>((resolve) => setTimeout(resolve, 100));

Fix 4: React 19 type changes

With @types/react 19, useRef requires an argument:

const ref = useRef<HTMLInputElement>();      // TS2554 in React 19 types
const ref = useRef<HTMLInputElement>(null);  // ok
const timer = useRef<number | undefined>(undefined);

Also createContext always needs a default value: createContext<User | null>(null).

Fix 5: event handlers and callbacks

Passing a function that requires an argument where the caller provides none, or calling a handler yourself without the event:

function onSave(e: React.MouseEvent) { /* ... */ }
onSave();                                   // TS2554
<button onClick={onSave}>Save</button>       // ok: React passes the event
<button onClick={() => onSave()}>Save</button> // TS2554

If the handler doesn't use the event, drop the parameter.

Fix 6: library types out of sync

If a library call that matches the docs fails, the installed type definitions are for a different version:

npm ls @types/node @types/express
npm install -D @types/express@latest

Libraries that ship their own types are fixed by upgrading the library itself. Check which overloads exist with "Go to Definition". When a function has overloads, TS reports the error against the closest overload, which may not be the one you intended.

Fix 7: class constructors and super()

class Base { constructor(public id: string) {} }
class Child extends Base {
  constructor() { super(); }   // TS2554
}

Pass the required arguments to super(...). Also note that new Child(...) is checked against the subclass constructor, not the base one.

Avoid silencing it with // @ts-ignore or as any: the runtime call will receive undefined for the missing argument.

Last updated 2026-11-07.