Webhook events

Reference for the events Sequence sends, the payload envelope, signature header, and delivery behavior.

This page is the reference for what Sequence sends and how. For a step-by-step integration walkthrough, see Set up webhooks.

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Request format

Sequence delivers webhooks as POST requests with Content-Type: application/json. Every payload has the same envelope:

{
  notificationType: string;
  sequenceAccountId: string;
  resourceType?: string;
  resourceId?: string;
  resource?: Record<string, any>;
}

The resource field contains the state of the resource that triggered the event.

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Example payload

A BILLING_SCHEDULE_CREATED delivery looks like this. The prices and phases arrays are simplified for readability; in real deliveries they contain the full pricing and phase structure for the schedule.

{
  "notificationType": "BILLING_SCHEDULE_CREATED",
  "sequenceAccountId": "019e6eb6-db30-7cf2-8017-06a5a2859e13",
  "resourceType": "BillingScheduleResponse",
  "resourceId": "019e6eb6-cd26-74eb-808b-e7a37f1c4ef1",
  "resource": {
    "id": "019e6eb7-0c24-765b-8446-6fb074f018d7",
    "status": "DRAFT",
    "startDate": "2026-04-27",
    "endDate": "2027-04-26",
    "customerId": "019e6eb7-353e-7ddf-a5ae-75f2d9509d6b",
    "recurrenceDayOfMonth": 1,
    "autoIssueInvoices": false,
    "rollUpBilling": false,
    "defaultDueDateDays": 30,
    "prices": [],
    "phases": [],
    "taxRates": [],
    "attachmentAssets": [],
    "integrationIds": [],
    "createdAt": "2026-04-27T17:04:11.601533Z",
    "updatedAt": "2026-04-27T17:04:11.601533Z"
  }
}

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Sequence-Signature header

Every webhook includes a Sequence-Signature header containing a timestamp and an HMAC signature:

Sequence-Signature: t=1748866120822,s=6be6887a470c20978427ff89941ebecb83b2804ceed66fd93b3afc00de2e9f11

• t is the delivery timestamp, in Unix milliseconds.
• s is an HMAC-SHA256 signature of ${t}.${rawBody}, computed using the webhook’s signing secret.

The timestamp is part of the signed payload, so receivers can reject deliveries with a stale t to mitigate replay attacks.

For working verification code, see Verify the signature in the integration guide.

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Delivery

• Acknowledgment. Sequence considers any 2xx response a successful delivery.
• Retries. Any non-2xx response causes Sequence to retry. Retries continue for up to 24 hours, with exponential backoff.

New event types may be added over time. Handlers should accept and ignore types they don’t recognize.

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Event catalog

Event	Resource type	Triggered when
CUSTOMER_CREATED	Customer	A customer is created
CUSTOMER_UPDATED	Customer	A customer is updated
CUSTOMER_ARCHIVED	Customer	A customer is archived
CUSTOMER_ALIAS_CREATED	CustomerAlias	An alias is added to a customer
CUSTOMER_ALIAS_UPDATED	CustomerAlias	An alias’s label is changed
CUSTOMER_ALIAS_DELETED	CustomerAlias	An alias is removed from a customer
INVOICE_CREATED	Invoice	An invoice is created
INVOICE_ISSUED	Invoice	An invoice is issued
INVOICE_UPDATED	Invoice	An invoice is updated
INVOICE_REMINDER_SENT	Invoice	A dunning payment reminder is sent to a customer
BILLING_SCHEDULE_CREATED	BillingSchedule	A billing schedule is created
BILLING_SCHEDULE_UPDATED	BillingSchedule	A billing schedule is updated
BILLING_SCHEDULE_ARCHIVED	BillingSchedule	A billing schedule is archived
CREDIT_NOTE_CREATED	CreditNote	A credit note is created
CREDIT_NOTE_UPDATED	CreditNote	A credit note is updated
CREDIT_NOTE_ISSUED	CreditNote	A credit note is issued
QUOTE_PUBLISHED	Quote	A quote is published
QUOTE_SIGNED	Quote	A quote is signed
QUOTE_ACCEPTED	Quote	A quote is accepted
MERCHANT_UPDATED	Merchant	Merchant-level settings are updated
WATCHTOWER_TASK_ASSIGNED	WatchtowerTask	A Watchtower review task is assigned to a user

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Customer alias events

Customer webhooks don’t include the customer’s aliases. To find out when an alias changes, subscribe to the alias events. Each one carries the single alias that changed.

Change	Event sent
Create a customer with aliases (POST /customers)	CUSTOMER_ALIAS_CREATED for each alias
Update a customer’s aliases (PUT /customers/{id}, or editing the customer in the dashboard)	CUSTOMER_ALIAS_CREATED for each alias added, CUSTOMER_ALIAS_DELETED for each alias removed
Create an alias (POST /customer-aliases, or linking an alias to a customer in the dashboard)	CUSTOMER_ALIAS_CREATED
Change an alias’s label (PUT /customer-aliases/{id})	CUSTOMER_ALIAS_UPDATED
Delete an alias (DELETE /customer-aliases/{id})	CUSTOMER_ALIAS_DELETED

These are sent alongside the customer events, not instead of them. For example, updating a customer to add an alias sends both CUSTOMER_UPDATED and CUSTOMER_ALIAS_CREATED. Archiving a customer sends CUSTOMER_ARCHIVED and no alias events.

The resource is the alias as the customer alias endpoints return it. label is left out when the alias has none, and deletedAt is only included in CUSTOMER_ALIAS_DELETED.

Webhooks can arrive out of order. Use updatedAt to order changes to the same alias: it’s set every time the alias is created, has its label changed, or is deleted.

{
  "notificationType": "CUSTOMER_ALIAS_CREATED",
  "sequenceAccountId": "af9b5988-1d7b-45f6-a188-326df5e59b24",
  "resourceType": "CustomerAlias",
  "resourceId": "01849e70-0a0f-72ca-ba07-5557dd734d43",
  "resource": {
    "id": "01849e70-0a0f-72ca-ba07-5557dd734d43",
    "sequenceAccountId": "af9b5988-1d7b-45f6-a188-326df5e59b24",
    "customerId": "01849e70-703e-705a-b59a-d3fd575587e0",
    "value": "external-customer-alias-123",
    "label": "CRM ID",
    "createdAt": "2022-10-01T00:00:00Z",
    "updatedAt": "2022-10-01T00:00:00Z"
  }
}