subscription.upgraded

When this fires

A subscriber switches to a higher-priced plan. Pro-ration is applied through the provider where supported.

Required ability

project-subscription:view-any — token must carry this at mint time to subscribe an endpoint to this event.

Payload

{
  "id": "evt_01HX...",
  "type": "subscription.upgraded",
  "created_at": "2026-05-22T10:05:00Z",
  "api_version": "2026-05-01",
  "project_id": "prj_01HX...",
  "data": {
    "subscription_id": "sub_01HX...",
    "subscriber_id": "usr_01HX...",
    "from_plan_id": "pln_01HX_basic",
    "to_plan_id": "pln_01HX_premium",
    "proration_amount": "12.50"
  }
}

Field reference

Field	Type	Notes
`id`	string ULID	Unique event id, prefixed `evt_`. Use for idempotent processing.
`type`	string	Always `subscription.upgraded` for this event.
`created_at`	ISO 8601 timestamp	Server-side emission time.
`api_version`	string	Webhook API contract version.
`project_id`	string ULID	Project this event belongs to.
`data.subscription_id`	string ULID	Subscription identifier.
`data.subscriber_id`	string ULID	Subscriber's project-scoped user id.
`data.from_plan_id`	string ULID	Plan id the subscription was on prior to the change.
`data.to_plan_id`	string ULID	Plan id the subscription is now on.
`data.proration_amount`	string	Pro-ration amount charged at switch time, in major units, as a string.

Caveats

The plan-direction is determined by the price comparison at switch time. Equal-price switches do not emit either upgrade or downgrade.
Trial windows do not carry across switches; if the destination plan has a trial it does not start.

subscription.downgraded — opposite direction.
payment.succeeded — pro-ration charge.
Subscription events overview — back to family overview.