Winning the contract is only half the job — getting paid on time is what keeps a government-contracting business alive. Federal payment runs on specific systems and rules, and small setup mistakes can stall an invoice for weeks. This guide covers the mechanics so cash flow doesn’t become the thing that sinks you.

How federal payment works at a high level

You perform, you submit an invoice through the government’s electronic system, the government accepts the work, and payment is issued to the bank account tied to your SAM.gov registration. Simple in theory — but each step has a system and a rule set.

The systems: WAWF and IPP

  • WAWF (Wide Area Workflow), part of the DoD’s PIEE environment, is where DoD contractors submit invoices and receiving reports. Most defense payments flow through it.
  • IPP (Invoice Processing Platform), run by Treasury, is the equivalent for many civilian agencies.

Which one you use depends on the contract and agency — the award and your contracting officer will tell you. Getting your account provisioned and your routing codes right before your first invoice avoids the classic first-month delay.

The Prompt Payment Act

The Prompt Payment Act requires the government to pay a proper invoice within a set window — commonly 30 days of acceptance — or owe interest. The key phrase is proper invoice: it must include the required elements (contract and line-item numbers, correct amounts, remittance info). An invoice missing a required field isn’t “late” — it’s rejected, and the clock restarts when you resubmit. Most payment delays are self-inflicted through incomplete invoices.

Retainage, financing, and progress payments

  • On some contracts the government may hold retainage until final delivery/acceptance.
  • Longer or larger efforts may allow progress payments or performance-based payments so you’re not floating all the cost.
  • Commercial-item contracts can include financing terms too.

Read the payment clauses in your contract — they determine your working-capital needs.

Set-up that prevents payment delays

  1. Keep SAM.gov active with correct banking (EFT) details — payment goes where SAM says.
  2. Get provisioned in WAWF or IPP early, with the right routing/DoDAAC codes.
  3. Send proper invoices — every required field, matched to the contract line items.
  4. Track acceptance; the Prompt Payment clock starts at acceptance, not submission.

How PursuitAI helps

PursuitAI helps on the front end that makes payment smooth: keeping your SAM.gov registration and company profile current (the identity and banking details payment relies on) and organizing your active contracts so the invoicing and modification details you need are in one place — so a lapsed registration or missing detail never holds up a payment.

A word of caution

Payment systems, clauses, and timelines are contract- and agency-specific, and the rules around proper invoices and financing are detailed. This is an overview — follow your contract’s payment clauses and your contracting officer’s instructions, and consult your accountant on financing and cash-flow decisions.