subscription.* events

Subscriber moved to a lower-priced plan.

When this fires

A subscriber is switched to a lower-priced plan on the same project. The plan assignment, currency, and stored price on the Subscriby subscription record are updated, and this event reports the move.

The switch does not itself perform a provider-side pro-ration or issue a credit. Any billing adjustment is whatever the provider does on the next cycle.

Caveats

  • No credit or refund is issued by this action. If you owe subscribers a mid-cycle credit on downgrade, apply it yourself through the provider.
  • Direction is decided by comparing the two plan prices, normalised to USD. Anything that is not strictly more expensive lands here, so a switch between two equally-priced plans emits this event, not subscription.upgraded.
  • Resource access tied to the higher tier may be revoked on the next renewal cycle.

Related events

  • subscription.upgraded: opposite direction.
  • member.resource_removed: emitted when premium-tier resources are detached.
postWebhooksubscription.downgraded

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.downgraded' required

The event name, always subscription.downgraded 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.