# Accounting systems

The [PNR_V3](/openapi/webhookeventapi/webhooks/paths/pnr_v3/post) is the recommended webhook for accounting integrations.
It provides the financial detail needed to validate transactions and update your accounting ledger at the individual booking level.

## Event flow

The following table describes a typical accounting system workflow using the [PNR_V3](/openapi/webhookeventapi/webhooks/paths/pnr_v3/post) webhook:

| Step | Operation  | Action and next steps |
|  --- | --- | --- |
| 1 | `BOOKING_TICKETED` | A booking is ticketed and payment method is charged.
Your system validates the financial data and posts the transaction to a general ledger as a revenue recognition entry. |
| 2 | `INVOICE_GENERATED` | An invoice PDF has been generated for the booking.
Your system can use this to retrieve and archive the invoice document for audit trails and compliance records. |
| 3 | `TICKET_VOIDED` | The traveler cancels within the void period.
Your system reverses the original ledger entry before the transaction is fully settled. |
| 4 | `TICKET_REFUNDED` | A refund is issued. Your system posts a revenue reversal entry to the general ledger. |