subscription.* events

Billing permanently failed; grace expired.

When this fires

A subscription's grace period ends without successful collection. The provider has given up retrying. Resource access is typically revoked shortly after.

This event is emitted for Stripe only; it depends on the provider reporting an unpaid subscription status. On every other provider, an abandoned subscription surfaces as subscription.expired once ends_at passes, with no preceding subscription.unpaid.

Caveats

  • After this event, the subscription is non-recoverable on its current terms; the subscriber must restart with a new subscription.
  • Expect subscription.expired and member.churned to follow.

Related events

  • subscription.past_due: predecessor inside the grace window.
  • subscription.expired: terminal state.
postWebhooksubscription.unpaid

Headers

SB-Signaturestring required

t=<unix seconds>,v1=<hex>: the HMAC-SHA256 of "<t>.<raw body>" under the endpoint's secret. Verify it before acting, and refuse a t more than 300 seconds from now. During a secret rotation a v0= signature under the previous secret may precede v1=.

SB-Event-Idstring required

The event's ULID, bare. The envelope's id is the same ULID prefixed evt_, so strip the prefix before comparing. Deduplicate on it: a retry carries the same id.

SB-Event-Namestring required

The event name, the same as the envelope's type.

Content-Typestring required

Always application/json.

User-Agentstring required

Always Subscriby-Webhooks/1.0.

Payload

idstring required

A ULID unique to the event, prefixed evt_. Every retry carries the same id, so it is the key to deduplicate on.

type'subscription.unpaid' required

The event name, always subscription.unpaid here.

created_atstring date-time required

When the event was emitted, server time, ISO 8601.

api_versionstring required

The contract version of the payload shape, 2026-05-01 today. A breaking change to a shape ships under a new version.

project_idstring uuid nullable required

The project the event belongs to; null for team-scoped and billing events.

Response

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

Changes

Webhooks have no change history: a webhook is keyed by its event name rather than a path and method, so no recorded change can name it.