Payload

All webhook payloads follow a consistent top-level structure with event-specific data nested within the data object.

invoiceIdstring

The invoice ID.

invoiceNumberstring

The human-readable invoice number.

invoiceStatusstring

Always "outstanding" for this event.

periodStartstring | null

ISO 8601 start of the billing period.

periodEndstring | null

ISO 8601 end of the billing period.

issueDatestring | null

ISO 8601 date the invoice was issued.

dueDatestring

ISO 8601 date the invoice was due — now in the past.

currencystring

The invoice currency code.

subtotalnumber

Subtotal in cents (100 = $1.00).

totalnumber

Total in cents (100 = $1.00).

customerIdstring

The customer ID. Returns your externalId if you provided one when creating the customer, otherwise returns the Commet publicId.

subscriptionIdstring | null

The subscription ID, if the invoice is linked to a subscription.

{
  "event": "invoice.overdue",
  "timestamp": "2026-05-02T06:00:00.000Z",
  "organizationId": "org_abc123",
  "mode": "live",
  "apiVersion": "2026-05-25",
  "data": {
    "invoiceId": "inv_n4o5p6",
    "invoiceNumber": "INV-0043",
    "invoiceStatus": "outstanding",
    "periodStart": "2026-04-25T00:00:00.000Z",
    "periodEnd": "2026-05-25T00:00:00.000Z",
    "issueDate": "2026-04-25T00:00:00.000Z",
    "dueDate": "2026-04-25T00:00:00.000Z",
    "currency": "usd",
    "subtotal": 9900,
    "total": 9900,
    "customerId": "user_123",
    "subscriptionId": "sub_1a2b3c4d"
  }
}

When this fires

A daily scan finds outstanding invoices whose dueDate is in the past and emits this event once per invoice. The idempotency key is derived from the invoice, so re-running the scan never sends a duplicate.

The invoice keeps its "outstanding" status — overdue is a fact about the due date, not a new status. If the invoice is later paid or voided, payment.received or invoice.voided reflects the outcome.

Use it to start your own dunning flow: email the customer, show an in-app banner, or flag the account for follow-up.