Sections

Introduction
General
Messages & Comments (old API)
To-do Lists (old API)
To-do List Items (old API)
Milestones
Time Tracking (old API)
Contact Management
Data Reference

Forum

Share thoughts, ask questions, and help fellow developers in the Basecamp API forum.

Example products

Check out some of the products that integrate with Basecamp via the API.

Messages & Comments API Calls

This is the newer, REST-based version of this API. If you are maintaining an older application, it might be using the legacy, non-RESTful version of this API, which can be found documented here.