Government Invoice Submission Guide: How to Get Paid on Federal Contracts

Quick Answer: How Do I Submit Invoices on Government Contracts?

Government contract invoices are typically submitted electronically through the Wide Area Workflow (WAWF) system or the Invoice Processing Platform (IPP). Invoices must include specific information like contract number, CLIN details, and supporting documentation. Properly submitted invoices are paid within 30 days under the Prompt Payment Act.

WAWF

Primary System

30 Days

Payment Due

Electronic

Submission

Interest

On Late Payment

Government Invoice Basics

Getting paid on government contracts requires submitting proper invoices through the correct channels. Unlike commercial customers where you might send a simple invoice by email, government invoicing has specific requirements, systems, and processes that must be followed.

Your contract specifies invoicing requirements, including what system to use, required documentation, and the approving officials. Understanding these requirements before you start work ensures you can bill promptly and get paid without delays.

Key Invoicing Concepts

→Proper Invoice: Invoice meeting all contract requirements
→CLIN: Contract Line Item Number - what you're billing for
→Acceptor: Government official who approves invoice
→Payment Office: DFAS or agency office that issues payment
→EFT: Electronic Funds Transfer - how you receive payment

WAWF Explained

The Wide Area Workflow (WAWF) is the primary electronic invoicing system for DoD and many civilian agency contracts. It provides a paperless process for submitting and tracking invoices.

Getting Started with WAWF

Ensure your banking and EFT information is current

Self-Register in WAWF

Create account at wawf.eb.mil

Complete Training

Take WAWF training before first invoice

Set Up Locations

Configure your CAGE codes and shipping locations

WAWF Invoice Types

✓2-in-1: Invoice and receiving report combined
✓Invoice Only: For cost-type contracts
✓Combo: Multiple documents in one submission
✓Progress Payment: For contracts with progress payment clause

Invoice Requirements

A "proper invoice" contains all information required for the government to process payment. Missing information results in invoice rejection and payment delays.

Required Invoice Information

→Contractor name and address
→Invoice date and unique invoice number
→Contract number and order number
→CLIN/SLIN description, quantity, unit price, total
→Shipping and payment terms
→Name and contact info of person to contact
→EFT banking information (from SAM)
→Any other contract-specific requirements

Fixed-Price Contracts

✓Bill against CLINs as milestones met
✓Deliver/performance acceptance required
✓Simpler documentation requirements

Cost-Reimbursement Contracts

✓Detailed cost breakdown required
✓Labor hours, rates, materials itemized
✓Cumulative costs to date

Invoice Submission Process

Following the correct process ensures your invoices are routed properly and paid promptly.

Step-by-Step Process

Complete Work/Delivery

Ensure deliverable is complete and accepted

Prepare Invoice

Include all required information and documentation

Submit in WAWF

Enter invoice and attach supporting docs

Government Review

Acceptor reviews and approves invoice

Payment Processing

DFAS/payment office processes EFT payment

Check Contract for Special Requirements

Always review your contract's payment clause for specific requirements. Some contracts require additional documentation, certifications, or approval workflows before invoices can be submitted.

Prompt Payment Act

The Prompt Payment Act requires the government to pay proper invoices within specific timeframes. Understanding your rights helps ensure timely payment.

Payment Timelines

→30 Days: Standard payment due date from proper invoice receipt
→7 Days: To notify contractor if invoice is improper
→14 Days: For meat, fish, and perishable products
→Interest: Automatically due on late payments

Your Rights Under Prompt Payment

✓Automatic interest on late payments (no need to request)
✓Interest calculated from day after due date
✓Rate is set by Treasury (changes semi-annually)
✓Can request payment status updates

Common Invoice Problems

Avoid these common issues that cause invoice rejections and payment delays.

Missing or Incorrect Contract Information

Wrong contract number, missing CLIN references, or incorrect pricing are top reasons for rejection. Double-check all contract references before submitting.

Incomplete Documentation

Cost-type contracts require detailed supporting documentation. Missing timesheets, receipts, or other backup causes delays. Attach all required documentation.

Billing Before Acceptance

Invoices submitted before deliverables are accepted will be rejected. Ensure government acceptance before invoicing, especially for fixed-price deliverables.

SAM Registration Issues

Expired SAM registration or incorrect EFT banking information prevents payment. Keep SAM current and verify banking information regularly.

Best Practices for Government Invoicing

Invoice Promptly

Submit invoices as soon as work is accepted. Delays in invoicing mean delays in payment. Establish a regular invoicing schedule (weekly or bi-weekly for ongoing work).

Maintain Good Records

Keep copies of all invoices, supporting documentation, and correspondence. Track invoice status in WAWF. Document all payment issues and resolutions.

Communicate with COR

Build a relationship with the Contracting Officer's Representative (COR) who approves invoices. Address any acceptance issues before submitting invoices. Quick communication resolves problems faster.

Monitor Invoice Status

Check WAWF regularly for invoice status. Follow up promptly on any rejections. Track payment dates and request interest on late payments.

Keep SAM Current

Set reminders to renew SAM registration before expiration. Update banking information immediately if it changes. Verify all information is accurate.

Frequently Asked Questions

What if my invoice is rejected?

Review the rejection reason in WAWF, correct the issue, and resubmit promptly. The payment clock restarts when the corrected invoice is received. Contact the COR if the rejection reason is unclear.

How do I check payment status?

Use WAWF to check if invoices have been accepted and forwarded for payment. For DoD contracts, myInvoice at DFAS shows payment status. Contact the payment office if payments are overdue.

Can I invoice for partial deliveries?

It depends on the contract terms. Some contracts allow partial billing as milestones are met. Others require full completion. Check your contract's payment clause for specific terms.

What if I haven't received interest on late payments?

Interest should be paid automatically, but sometimes isn't. Contact the contracting officer with documentation of the late payment and request the interest owed. You are entitled to interest by law.

Do all agencies use WAWF?

DoD uses WAWF. Some civilian agencies use the Invoice Processing Platform (IPP) or agency-specific systems. Your contract specifies the required invoicing system. Some contracts still accept email invoices.

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