REST v2 Custom Fields vs XML-RPC - Current Status

API Q&A
1

Hi all,

The table below gives the current status (December 21st 2025) of the REST v2 Custom Fields.

Explanation of the table columns.

  • Response = Custom Fields appear in the response when retrieving one or more records.
  • Query = Ability to Query on the Custom Field (Not currently supported in REST v2).
  • Update = Ability to Add or Update the Custom Field for the Record.
  • Creation = Ability to create the Custom Field for the entity via the API.
Item Response Query Update Creation
Affiliate No No No Yes
Appointment No No No No
Company No No No No
Contact Yes No Yes No
Note No No No Yes
Opportunity Yes No Yes Yes
Order No No No Yes
Subscription No No No Yes
Task No No No Yes

In comparison to XML-RPC, you can retrieve, query, update and create across all entities without a problem.

This table will be updated when Keap updates the API with future changes.

2

Hi Pav, all those gaps have been noted, and I’ll keep you updated as they get resolved. As you know, querying isn’t planned in v2 at the moment, but I’ll share any updates as they come!

3

@OmarAlmonte - I recommend that you add Custom Fields Querying to the Issue Tracker.

In the Contacts / Orders Search you can create a saved search based on the Custom Fields, which in turn can be run via the API.

So what is the difference between running a saved search and doing it via the API? It will be running the same database queries.

1 Like
4

@Pav It was decided not to support custom field filtering in v2 due to performance concerns. This is still an open question for future versions, but as of now there are no plans to include it in v2.

5

@OmarAlmonte - Sorry, but I do not understand your team thinking here.

I can go in and make a Saved Search with a particular Custom Field set. That search can be run via the REST API. The only difference is that you have to manually setup the search.

But your team has partially added other endpoints to add, update and delete custom fields, like for the Orders.

I am sure other developers will come along soon to request this requirement.