What is an accounts receivable (A/R) aging report?

For an accounting firm, the A/R aging report answers a simple question: who owes us money, and for how long? Each client's unpaid invoices are sorted into age buckets, with totals per client and for the firm.

The older an invoice, the less likely it is to be paid in full, so the report tells partners where to follow up first. Firms often review it weekly in busy season and monthly the rest of the year.

Read it alongside work in progress (WIP), the work done but not yet billed, to see the full path from work performed to cash collected.