If you invoice the Department of War, two changes from 2026 matter right now. Since Oct. 1, 2026, DoD contracting officers must use PIEE's Solicitation Module for most unclassified solicitations, so you need an active PIEE account just to bid. And if DCMA administers your contract through MOCAS, DFAS has consolidated MOCAS into one database, which leaves a single pay DoDAAC, HQ0339, to select when you invoice.

WAWF isn't going away. It's still the invoicing application inside PIEE, and DFARS still requires DoD contractors to submit payment requests through it. What's changing is around it: how you get to the solicitation, which pay office code you pick, and how much the rules can help when a payment runs late.

Change 1: PIEE Is Now the Front Door to Bidding

PIEE, the Procurement Integrated Enterprise Environment, is DoD's procure-to-pay system. DFAS describes it as "often referred to as WAWF," and it holds WAWF, myInvoice, Electronic Data Access, and other tools.

The DFARS guidance on availability of solicitations now says that effective Oct. 1, 2026, contracting officers "shall use the Solicitation Module for publishing unclassified solicitations and for receiving offers and quotes," unless an exception applies. The module also posts the required notice to SAM, so you'll still see the opportunity there.

The module isn't required for single-source requests, simplified acquisition procedures, emergency acquisitions, or actions awarded outside the United States. It can't yet be used for broad agency announcements or for orders under existing contracts and agreements.

So for most competitive DoD solicitations, you'll download the documents and submit your offer in PIEE. Set up your PIEE vendor account and roles before you find a bid you want, not the week it's due.

Change 2: One Pay DoDAAC for MOCAS Contracts

A DoDAAC is a six-character code that identifies a DoD unit, activity, or office. When you create an invoice in WAWF, you fill in several of them, starting with the Pay Official DoDAAC, the office that pays you. To find it, look in your contract. DoD contracts that use WAWF include a payment instructions clause with a routing data table. The contracting officer fills in the codes, and the clause tells you to use that table to fill in the WAWF fields.

Here's the 2026 change. On July 7, 2026, DFAS announced that DCMA would consolidate MOCAS, the system that pays many DCMA-administered contracts, into a single database at the end of August 2026. Contracts in pay office HQ0338 moved into HQ0339 between February and August. DFAS says the result is one pay DoDAAC, HQ0339, to select when invoicing.

If your contract is paid through MOCAS and your paperwork still shows HQ0338, don't guess. Call the DFAS Industrial Base Pay Support Center at 800-756-4571, option 1, which DFAS lists for questions on the consolidation.

Keep Your PIEE Account Ready

A PIEE problem usually shows up at the worst time: the day an invoice is due or a proposal closes. A few habits prevent most of it.

1. Log in regularly: Don't let the account sit for months between invoices.
2. Keep roles current: Your account needs the right vendor roles for invoicing and, now, for responding to solicitations.
3. Keep a backup user: If one person holds every role and leaves, you can't invoice.
4. Know who to call: For technical issues, DLA lists the PIEE Help Desk at 866-618-5988.

What a Proper Invoice Needs

Payment timing under the Prompt Payment rules starts with a proper invoice. Treasury's guidance says the payment period starts when the agency receives a proper invoice with all required information.

The Prompt Payment clause lists what a proper invoice includes:

1. Who you are: Your company name and address, and the name and address of the payee.
2. What you're billing: Invoice date and number, contract and order number, and line item numbers.
3. The details: Description, quantity, unit of measure, and unit and extended price of what you delivered.
4. Terms and contacts: Shipping and payment terms, and a contact for questions about a defective invoice.
5. Payment and tax data: Your taxpayer ID if the contract requires it, electronic funds transfer information, and any other documentation the contract requires.

If something is missing, the invoice is improper. Treasury says the agency must return an improper invoice no later than seven days after it receives it.

When Payment Is Late: Prompt Payment Interest

Under the Prompt Payment clause, the due date is generally the later of the 30th day after the billing office receives a proper invoice or the 30th day after the government accepts the work, unless your contract sets a different date.

If the government pays late, it owes you interest, and it pays that interest automatically. You don't have to ask. Treasury sets the rate every six months. For July 1 to Dec. 31, 2026, it's 4.75%.

What to Do When the CO or COR Goes Quiet

Many payment delays aren't at DFAS at all. The invoice is sitting in WAWF waiting for someone on the government side to accept the work.

Work through it in order:

1. Check the status yourself: DFAS's myInvoice, inside PIEE, shows paid and unpaid invoice status around the clock. Confirm whether the invoice is waiting on acceptance, rejected, or in payment.
2. Read any rejection reason: A rejected invoice comes back with a reason. Fix that and resubmit rather than resubmitting the same document.
3. Contact the acceptor: If the invoice is waiting on acceptance, email the COR or the acceptor named on the invoice. Keep it short: invoice number, date submitted, and a polite request to accept or tell you what's missing.
4. Escalate to the contracting officer: If a week passes with no answer, copy the contracting officer. The CO is the person with authority over the contract.
5. Call the paying office: If the invoice was accepted and still isn't paid, contact DFAS. Have your contract number, invoice number, and pay DoDAAC ready.

Keep a record of every message. If the delay turns into a dispute, your timeline matters.

Frequently Asked Questions

Is WAWF going away?

No official DoD or DFAS page we found says so. WAWF is still the invoicing application inside PIEE, and DFARS still requires DoD contractors to submit payment requests and receiving reports through it.

Do I need a PIEE account to bid on DoD work?

For most unclassified DoD solicitations issued since Oct. 1, 2026, yes. DFARS guidance requires contracting officers to use PIEE's Solicitation Module to publish them and receive offers, with exceptions such as simplified acquisitions and single-source requests.

Where do I find my pay DoDAAC?

In the payment instructions clause in your contract, which includes a routing data table filled in by the contracting officer. For MOCAS-paid contracts, DFAS says consolidation leaves one pay DoDAAC, HQ0339.

When does the government have to pay me?

Generally by the 30th day after the billing office receives a proper invoice or the 30th day after acceptance, whichever is later, unless the contract sets a different date.

What's the Prompt Payment interest rate right now?

Treasury set it at 4.75% for July 1 to Dec. 31, 2026. It's paid automatically on late payments.

View full FAQ page: https://usfcr.com/resources/faq/

Get Your Systems Ready Before the Next Award

For the bigger picture on billing, see what your accounting team needs to know about invoicing the government and what happens after you submit a federal proposal.

USFCR has served over 500,000 businesses, and our clients have won over $1.9 billion in contracts. If you want help getting your registrations and systems in order for DoD work, speak to a USFCR Registration & Contracting Specialist at (866) 216-5343.

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