Reviewing for Accurate Invoice Prices
Comparing prices on supplier invoices to original purchase order prices provides evidence
for testing the management assertion of accuracy. Significant discrepancies between
expected prices and the prices actually charged may be due to clerical errors,
failure to review supporting documents before authorizing payment, or accounts payable
personnel exceeding their authority in dealing with price discrepancies.
Traditionally, auditors verify pricing accuracy by comparing invoice prices with the
purchase orders on a sample basis only. Of the thousands of invoices processed during
the period, perhaps only one or two hundred can be tested manually.