Reconciling the payables ledger against the creditors balance feels like a search for errors and is mostly an exercise in categorising timing. Sorting the differences into three known groups before investigating anything explains most of them in minutes and leaves a much shorter list of genuine unknowns, which can then be investigated properly.
Goods received, not invoiced
Deliveries recorded against orders where the supplier has not billed yet. A real obligation, usually accrued rather than sitting in payables, so it produces a difference in a predictable direction. Its size reflects how promptly your suppliers invoice and how promptly receipts are recorded, both of which you can observe and influence.
Invoiced, not posted
Invoices sitting in the queue, unapproved or in exception, and therefore not in the ledger. This is your operational backlog expressed in money. Treat it as a process signal as well as a reconciling item: a growing figure here is usually news worth passing on before month end rather than after.
In transit and misallocated
Payments made and not yet cleared, and credits applied against the wrong invoice. Both are timing or allocation rather than error and both normally resolve within a period. What remains after these three categories is the genuine unknown, and a short list investigated properly beats a long list skimmed.
Questions people ask about reconciling accounts payable
How often should this be done?
Monthly. Less often and the differences accumulate until categorising them is itself a project.
Who decides the accounting treatment?
Your accountant. Payables produces accurate detail and dates; the treatment is decided elsewhere.
What if a difference persists for months?
Investigate it as an item. Real errors hide among timing differences precisely by persisting quietly.