# API v3 stops working

Calls to /v3/* on Omnisend API stop working on December 31, 2027.

- API: Omnisend API (api.omnisend.com)
- Kind: Endpoint removal
- Takes effect: December 31, 2027
- Calls after that day: fail
- Calls it hits: `/v3/*`
- Source: [Announcement](https://api-docs.omnisend.com/v3/reference)
- Page: https://www.okapi.bot/providers/omnisend-api/breaking-changes/api-v3-stops-working/

## What to use instead

Move to the v2026-03-15 API: base path https://api.omnisend.com/api/ (contacts, products, categories, batches, events), Authorization: Omnisend-API-Key {key} and an Omnisend-Version: 2026-03-15 header on every request.

## Omnisend API's words

> The v3 API is deprecated and will be sunset on December 31, 2027 .