---
title: "Sign up with SMS OTP"
method: POST
path: "/signup/passwordless/sms"
tags: ["authentication"]
---

# Sign up with SMS OTP

`POST /signup/passwordless/sms`

Register a new user account using SMS OTP authentication. Sends a one-time password to the specified phone number.
Use this endpoint to explicitly register a new account. When `AUTH_DISABLE_AUTO_SIGNUP` is enabled, this is the only way to register through this method.

## Request body

- SignUpPasswordlessSmsRequest
  - `phoneNumber` string, required — Phone number of the user
  - `options` SignUpOptions
    - `allowedRoles` string[]
    - `defaultRole` string
    - `displayName` string
    - `locale` string — A two or three characters locale
    - `metadata` object
    - `redirectTo` string, uri

## Response `200`

OTP sent to the user's phone number. To prevent account enumeration, this response is also returned without side effects when the phone number is already registered.

- 'OK'

## Other responses

- `default` — An error occurred while processing the request

## Changes

- **2026-06-24** `0fc5fd589dbf` — 1 warning
  - added the new `otp-too-many-attempts` enum value to the `error` response property for the response status `default`
- **2026-04-20** `b39086c84b43` — 1 info
  - endpoint added
- **2025-10-09** `2bb5c4e40463` — 1 breaking
  - api path removed without deprecation

[Change history](https://skmtc.dev/nhost/apis/nhost-authentication-api/changes/signup/passwordless/sms/post.md)

---

[API](https://skmtc.dev/nhost/apis/nhost-authentication-api.md) · [All operations](https://skmtc.dev/nhost/apis/nhost-authentication-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/nhost/nhost-authentication-api/revisions/a5c0d88b55c4/schema)