---
title: "Start phone sign-in (send SMS code)"
method: POST
path: "/users/phone-sessions"
tags: ["Public", "PhoneSessions"]
---

# Start phone sign-in (send SMS code)

`POST /users/phone-sessions`

## Request

- Base URL: `https://api.purplegrain.com/api/v1`
- URL: `https://api.purplegrain.com/api/v1/users/phone-sessions`
- Auth: none declared

Passwordless phone sign-in, step 1: sends a 6-digit SMS one-time code
(self-issued) to the given Australian mobile. Works for numbers with
or without an existing account — verifying a new number creates the
account (phone sign-in is also phone sign-up). Always returns **204**;
the response never reveals whether a number has an account. Re-sends are
rate-limited per number and per IP.

## Request body

- object
  - `mobile` string, required: Australian mobile in any common format.

## Response `204`

Accepted (a code was sent if the number and rate limits allow).

## Other responses

- `403`: Forbidden — first-party only; refused to an API key or an assistant's token.

---

[API](https://skmtc.dev/purplegrain/apis/purple-grain-api.md) · [All operations](https://skmtc.dev/purplegrain/apis/purple-grain-api/llms.txt) · [OpenAPI document](https://skmtc.dev/purplegrain/apis/purple-grain-api/revisions/29c5c990d66e?raw)