---
title: "A capped season ticket sold its last seat."
method: POST
path: "pass_series.seats_exhausted"
tags: ["pass_series.* events"]
---

# A capped season ticket sold its last seat.

`POST pass_series.seats_exhausted` (webhook)

### When this fires

A purchase took the last seat on a series with a **Seat Limit**. The season is now sold out: its portal card reads **Sold out**, but a checkout already in flight is not blocked; the seat cap is only claimed once the payment lands, so a late buyer can pay, be given nothing, and be told to ask the organiser for a refund. Treat this event as the cue to stop promoting the season yourself.

Fires at the transition, once. An endpoint told this on every subsequent read would be told a fact rather than an event.

### Caveats

- **Sold out is not permanent.** A seat is released when a holder cancels or is refunded, and the series goes back on sale, at which point a later purchase can exhaust it again and emit this a second time. Treat it as a state change, not a terminal state.
- Only holders who actually hold the series consume a seat. A checkout that was started and abandoned, or a payment that never cleared, does not.
- A series with no **Seat Limit** never emits this at all.
- Raising the cap does not emit anything. If you are tracking availability, read `seats_remaining` on the plan rather than inferring it from this event alone.

### Related events

- `pass_series.purchased`: every purchase, each carrying `seats_remaining`.
- `plan.deactivated`: the series coming off sale for good once its dates have run.

## Headers

- `SB-Signature` string, required
- `SB-Event-Id` string, required
- `SB-Event-Name` string, required
- `Content-Type` string, required
- `User-Agent` string, required

## Payload

- object: The envelope every event is delivered in.
  - `id` string, required: A ULID unique to the event, prefixed `evt_`. Every retry carries the same id, so it is the key to deduplicate on.
  - `type` 'pass_series.seats_exhausted', required: The event name, always `pass_series.seats_exhausted` here.
  - `created_at` string, date-time, required: When the event was emitted, server time, ISO 8601.
  - `api_version` string, required: The contract version of the payload shape, `2026-05-01` today. A breaking change to a shape ships under a new version.
  - `project_id` string, uuid, nullable, required: The project the event belongs to; null for team-scoped and billing events.
  - `data` object, required: The event-specific payload. Keys that do not apply to a given emission are omitted rather than sent as null, so check for presence.
    - `plan_id` string, uuid, required: The series plan that sold out.
    - `plan_name` string, required: Its name.
    - `seat_cap` integer, required: The limit that was reached.
    - `seats_taken` integer, required: Holders counted against it.
    - `last_subscription_id` string, uuid, required: The purchase that took the final seat.

## Acknowledgement `2XX`

Your endpoint acknowledged the delivery. Any 2xx status within 30 seconds marks it delivered; the response body is ignored.

## Other responses

- `default`: Any other status, a connection failure, or no answer within 30 seconds counts as a failed attempt. The delivery is retried 8 times, after 10 seconds, 30 seconds, 2 minutes, 10 minutes, 1 hour, 6 hours, 1 day, 3 days; the last failure dead-letters it, and it can be retried from the dashboard or `POST /v1/webhook-deliveries/{delivery}/retry`. After 20 consecutive failures the endpoint is paused until it is resumed.

---

[API](https://skmtc.dev/memberpass/apis/subscriby-rest-api.md) · [All operations](https://skmtc.dev/memberpass/apis/subscriby-rest-api/llms.txt) · [OpenAPI document](https://skmtc.dev/memberpass/apis/subscriby-rest-api/revisions/59c4df91d764?raw)