---
title: "POST /connections/{phoneNumber}/on-whatsapp"
method: POST
path: "/connections/{phoneNumber}/on-whatsapp"
tags: ["Connections"]
---

# POST /connections/{phoneNumber}/on-whatsapp

`POST /connections/{phoneNumber}/on-whatsapp`

## Request

- Base URL: `http://localhost:3025`
- URL: `http://localhost:3025/connections/{phoneNumber}/on-whatsapp`
- Auth: API key in header `x-api-key`

Check if phone numbers are registered on WhatsApp

## Path parameters

- `phoneNumber` string, required

## Request body

- object
  - `jids` string[], required: Array of phone numbers to check if they are on WhatsApp

## Response `200`

Phone numbers checked successfully

- object
  - `data` object[]
    - `jid` string: WhatsApp JID of the phone number
    - `exists` boolean: Whether the phone number is registered on WhatsApp

## Other responses

- `403`: Forbidden — the API key does not own this connection. Returned when a connection is bound to a different API key.
- `421`: Misdirected Request — in cluster mode, this instance does not own the connection. The owning instance id is in the x-baileys-owner header; a proxy re-routes the request there. Not returned for the explicit-takeover routes: POST /connections/{phoneNumber}, /import-session and /restart.

## Changes

- **2026-08-15** `533b3360e2e4`: 5 breaking, 46 warning, 4 info
  - the response property `data` became optional for the status `200`
  - the `data` response's property type changed from `object` to `array` for status `200`
  - removed the required property `data/key` from the response with the `200` status
  - removed the required property `data/messageTimestamp` from the response with the `200` status
  - …51 more
- **2026-08-15** `80b5396ef493`: 2 info
  - added the non-success response with the status `422`
  - added the success response with the status `202`
- **2026-06-16** `da89554d2e38`: 13 info
  - added the non-success response with the status `409`
  - added the non-success response with the status `421`
  - added the optional property `data/capping_status` to the response with the `200` status
  - added the optional property `data/cycle_end_timestamp` to the response with the `200` status
  - …9 more
- **2026-03-20** `8632adf0286b`: 1 breaking, 41 info
  - the `data` response's property type changed from `array` to `object` for status `200`
  - added the non-success response with the status `403`
  - added the non-success response with the status `404`
  - added the non-success response with the status `500`
  - …38 more
- **2025-08-18** `fe6fd6d0ca88`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/fazer-ai/apis/fazer-ai-baileys-api/changes/connections/:phoneNumber/on-whatsapp/post.md)

---

[API](https://skmtc.dev/fazer-ai/apis/fazer-ai-baileys-api.md) - [All operations](https://skmtc.dev/fazer-ai/apis/fazer-ai-baileys-api/llms.txt) - [OpenAPI document](https://skmtc.dev/fazer-ai/apis/fazer-ai-baileys-api/revisions/322af11b310e?raw)