> ## Documentation Index
> Fetch the complete documentation index at: https://commet.co/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# invoice.upcoming

> Predictive event fired once, 3 days before a subscription renews.

## When this fires

A daily scan finds active subscriptions renewing within the next 3 days and emits this event once per renewal. The idempotency key is derived from the subscription and the renewal date, so re-running the scan never sends a duplicate.

Subscriptions with a scheduled cancellation are excluded — no renewal invoice will be issued for them.

Use it to notify the customer before they are charged. The payload intentionally carries no amount: usage-based charges are only final at renewal time, when `invoice.created` delivers the actual invoice.


## OpenAPI

````yaml /openapi/en/webhooks/2026-08-27.json webhook invoice.upcoming
openapi: 3.1.0
info:
  title: Commet Webhooks
  version: '2026-08-27'
  description: >-
    Outbound webhook events emitted by the Commet API. Each event is delivered
    as a signed POST to your configured endpoints.
servers: []
security: []
paths: {}

````

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