generated: '2026-07-18'
method: searched
source: https://developer.bill.com/docs/webhooks
docs: https://developer.bill.com/docs/webhooks
spec_type: Webhooks
description: >-
  BILL (Divvy / Spend & Expense) publishes a webhook event surface. Subscribers
  create event subscriptions (up to 10 per organization) against a full events
  catalog (GET /v3/events/catalog). Notifications are signed with an HMAC-SHA256
  security key delivered as the x-bill-sha-signature header, and failed
  deliveries are retried with exponential backoff.
delivery:
  transport: HTTP POST to subscriber notificationUrl
  signing: HMAC-SHA256, header x-bill-sha-signature
  security_key: One-time securityKey returned on subscription create; rotatable via createNewSecurityKey
  retries: Exponential backoff on delivery failure
  subscription_limit: 10 subscriptions per organization
management_operations:
  - operationId: geteventcatalog
    summary: Get the complete list of available events you can subscribe to
  - operationId: createsubscription
    summary: Create a new event subscription (multiple events per request)
  - operationId: getallsubscriptions
    summary: Get a list of all created subscriptions
  - operationId: geteventsforsubscription
    summary: Get event notifications sent for a subscription (retry troubleshooting)
  - operationId: resendevent
    summary: Resend an existing event notification
  - operationId: sendtestevent
    summary: Generate a test event notification to the subscriber URL
  - operationId: createnewsecuritykey
    summary: Rotate the HMAC signing key for a subscription
event_families:
  - family: Spend & Expense (Divvy)
    events:
      - name: spend.three-ds-challenge.created
        payload: https://developer.bill.com/docs/spend-expense-3ds-challenge-notification-payload
        summary: A 3D Secure challenge was triggered for a card transaction
      - name: Spend & Expense transaction
        payload: https://developer.bill.com/docs/spend-expense-transaction-notification-payloads
      - name: Spend & Expense reimbursement
        payload: https://developer.bill.com/docs/spend-expense-reimbursement-notification-payload
      - name: Card account
        payload: https://developer.bill.com/docs/card-account-webhook-notification-payloads
  - family: BILL AP/AR/network
    events:
      - name: Vendor
        payload: https://developer.bill.com/docs/vendor-webhook-notification-payloads
      - name: Vendor auto-pay
        payload: https://developer.bill.com/docs/vendor-autopay-webhook-notification-payloads
      - name: AP bill
        payload: https://developer.bill.com/docs/bill-webhook-notification-payloads
      - name: AP payment
        payload: https://developer.bill.com/docs/payment-webhook-notification-payloads
      - name: Bank account
        payload: https://developer.bill.com/docs/bank-account-webhook-notification-payloads
      - name: AR invoice
        payload: https://developer.bill.com/docs/invoice-webhook-notification-payloads
      - name: Risk verification
        payload: https://developer.bill.com/docs/risk-verification-webhook-notification-payloads