List API Documentation

This page summarizes information on the List API endpoints that Act-On Software offers to developers and customers. For information on working directly with contacts in a list, please see the Contact API documentation You can click through to find details on each endpoint. For questions, please post to our developers forum.

All API calls to Act-On Software should be made to the "" base domain.

Working with lists

Using the Act-On APIs, you can create, update, and merge into lists. For this functionality, you need to know how to get the ID of your newly created list or of any list(s) with which you want to work, and you need to understand how to create and use both uploadSpecs and mergeSpecs.

Any time that you create a new list, the list ID is returned. Once you create a list using POST /api/1/list with uploadspecs (to indicate the headings/system that you need), you can merge your list data using a csv file.

To get the ID for all lists that exist within any Act-On account, use GET list listing (listed in the endpoints table below).

Method Name


  • Get List of Assets

  • Download a List

  • Create a New List

  • Update a List

  • Get List Upload Status

  • Delete a List

  • Delete Records from List

  • Get Hard Bounce List

  • Get Spam Complaint List

  • Get Opt-Out List

  • Update Opt-Out List

  • uploadspecs

  • mergespecs

  • Get List Rejected Records

  • Remove Opt-Outs