Purchase order (PO)

A purchase order is a document committing to buy materials or subcontracted work at agreed quantities and prices, tied to a job.

POs turn intended spend into a committed cost and create the paper trail that lets you match a vendor's invoice (and later a bank charge) back to the right job. They're the backbone of accurate, real-time job costing.

Related terms

  • Committed costA committed cost is money you're obligated to spend but haven't been billed for yet — typically an open purchase order or signed subcontract.
  • Cost codesCost codes are standardized buckets (e.g. materials, labor, subs, equipment — often by phase) used to categorize every job cost so you can compare actuals to the estimate.
  • Job costingJob costing is tracking the actual costs of a specific job — materials, labor, subs, and other expenses — against what you estimated, so you know the real profit on that job.