---
agentTools:
  projectIndex: https://developer.bill.com/llms.txt
---

# New v3 API endpoints for MFA

We have introduced a set of Multi-Factor Authentication (MFA) API endpoints. There are two stages in the BILL MFA process.

1. **MFA setup**: Add a valid phone number for setting up MFA in the organization (with `POST /v3/mfa/setup`), and then complete the setup by validating the entered phone number (with `POST /v3/mfa/validate`). At this point, the phone number is registered for the MFA sign in operation.

2. **MFA sign in**: Generate an MFA challenge (with `POST /v3/mfa/challenge`), and then complete MFA sign in by validating the MFA challenge (with `POST /v3/mfa/challenge/validate`). At this point, your API session is MFA trusted.

| Operation                                                                           | API endpoint                      |
| :---------------------------------------------------------------------------------- | :-------------------------------- |
| [Add phone for MFA setup](https://developer.bill.com/v3/reference/setup)            | `POST /v3/mfa/setup`              |
| [Validate phone for MFA setup](https://developer.bill.com/v3/reference/validate)    | `POST /v3/mfa/validate`           |
| [Generate MFA challenge](https://developer.bill.com/v3/reference/generatechallenge) | `POST /v3/mfa/challenge`          |
| [Validate MFA challenge](https://developer.bill.com/v3/reference/validatechallenge) | `POST /v3/mfa/challenge/validate` |