# /v1/reservations/{}/custom-fields stops working

Calls to /v1/reservations/{}/custom-fields* on Guesty Open API stopped working on May 31, 2026.

- API: Guesty Open API (open-api.guesty.com)
- Kind: Endpoint removal
- Announced: November 20, 2025
- Takes effect: May 31, 2026
- Calls after that day: fail
- Calls it hits: `/v1/reservations/{}/custom-fields*`
- Source: [Announcement](https://open-api-docs.guesty.com/docs/custom-reservation-fields-migration)
- Page: https://www.okapi.bot/providers/guesty-open-api/breaking-changes/v1-reservations-custom-fields-stops-working/

## What to use instead

Call the same operations under /v1/reservations-v3/{reservationId}/custom-fields (GET, PUT, and GET or DELETE /{fieldId}) and read the reservationId and customFields wrapper they return.

## Guesty Open API's words

> After this date, the Custom Reservations Fields v2 resource will be permanently removed, and all associated API calls will fail.