Under the Hood
API Reference

API Reference

This document describes the resources that make up the official FOSSBilling API.

A more complete guide to using the API is in progress. At this moment there are no major breaking API changes between the last BoxBilling release and current FOSSBilling preview builds and you can also refer to the BoxBilling API documentation.


All API access is over HTTPS, and uses the following endpoint: (opens in a new tab)

The same endpoint can be used for both Admin and Client API calls.

All Requests are made via POST method

All data is sent and received as JSON.

All methods names are lowercase and words are separated by an underscore.

Blank fields are included as null instead of being omitted.

All timestamps are returned in ISO 8601 format.


Usernames are admin or client

The authentication password is a token which can be retrieved from the FOSSBilling Admin area.

The API uses cookies to store sessions.


All Requests are made via the POST method.

Data can be sent as JSON string or POST form.

All data is received as JSON.