How split purchase orders hide from routine samples

Routine accounts payable samples often select invoices above a monetary threshold. That design is sensible for materiality in a financial statement audit. It is less useful when buyers deliberately keep each line below the approval band that would trigger a second signature.

What we look for instead

In procurement compliance work we rebuild populations by vendor and by calendar week, not only by invoice amount. Clusters of near-threshold orders to the same supplier within a short window are the first signal. We then pull the related purchase requisitions and chat or email approvals that sat outside the formal system.

A practical cut

Ask for all purchase orders between 70% and 99% of each approval threshold for the quarter. The list is rarely long, and it concentrates attention where splitting is most profitable for a hurried buyer. Pair that list with vendor concentration reports so one-off legitimate urgencies do not drown the sample.

Limits of the method

Not every near-threshold order is misconduct. Project phasing and genuine partial deliveries explain many cases. The audit value is in documenting whether the second signature rule was consciously avoided — and whether policy language needs tightening around “urgency” exceptions.