---
title: "Lookup an existing user"
method: GET
path: "/payout/user/lookup"
tags: ["User"]
---

# Lookup an existing user

`GET /payout/user/lookup`

This **GET** endpoint is used to lookup whether a user with the provided email and first name exists in the MassPay system. <br> To use this endpoint, you need to provide the `email`, `first_name`, and `internal_user_id` as Query parameters in the URL. <br> The endpoint will then search for the user based on the provided information and return a JSON response indicating whether the user exists or not. If the user exists, the response will also contain the user's details, `user_token`, `first_name`, `last_name` and `internal_user_id`.

## Query parameters

- `email` string, required
- `first_name` string, required
- `internal_user_id` string, required

## Headers

- `Idempotency-Key` string

## Response `200`

Found a matching user

- FoundUser — Response object when a user is found
  - `user_token` string, required — The token of the found user
  - `first_name` string, required — First name of the user
  - `last_name` string, required — Last name of the user
  - `internal_user_id` string, required — A client-defined identifier for the user. This is the unique ID assigned to the user on your system. Max 75 characters. Allows letters, numbers, and + , - . / _ ~ |
  - `status` 'ACTIVE' | 'LOCKED' | 'DEACTIVE' | 'CLOSED', required — The status of the user

## Other responses

- `400` — Bad request.
- `401` — Unauthorized.
- `403` — Forbidden.
- `404` — Not found.
- `405` — Method Not Allowed.
- `500` — Internal server error.
- `504` — Gateway Time-out.

---

[API](https://skmtc.net/masspay/apis/masspay-api.md) · [All operations](https://skmtc.net/masspay/apis/masspay-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/masspay/masspay-api/revisions/c03b61a6a551/schema)