FAR 33.208 Guide: When Interest Starts on Federal Claims
When construction contractors face unresolved payment disputes on federal projects, the financial impact extends beyond direct jobsite labor and materials. Delayed settlement funds create cash flow strain, making statutory interest an essential component of financial recovery. Under federal contracting rules, the government must pay interest on a contractor claim for the amount found due and unpaid. However, this interest does not start automatically when an unexpected project expense occurs or when an informal request for adjustment is submitted. Navigating FAR 33.208 on Acquisition.GOV requires estimators and project managers to understand the precise triggers that start the interest clock, how rates are adjusted over time, and how proper claim delivery protects entitlement.
Checklist Item: Confirming Official Receipt by the Contracting Officer
The primary baseline for calculating claim interest is the formal receipt of the claim document by the government. Under federal procurement standards, the government shall pay interest on the amount found due and unpaid starting from the date the contracting officer receives the claim. If the claim requires certification under subsection 33.207(a), that certification must accompany the submission for the receipt date to trigger the interest clock.
For prime contractors and specialty trade subcontractors seeking pass-through recovery, securing undeniable verification of this receipt date is critical. Informal correspondence, verbal disputes raised during site meetings, and routine pay applications do not satisfy the threshold of a formal claim under the Disputes statute. Until the contracting officer officially receives the formal claim package, the interest clock remains stopped. Documenting proof of physical or electronic delivery establishes the starting date on which any future interest calculation depends.
Checklist Item: Assessing Whether Payment Is Due at a Later Date
While contracting officer receipt is the standard starting benchmark, federal rules include an explicit secondary condition regarding payment timing. Interest begins running from the date the contracting officer receives the claim or the date payment otherwise would be due, whichever date occurs later, continuing until the date of payment. Contractors must review their contract terms to determine whether the underlying adjustment involves amounts that would not have matured into payable obligations on the day of receipt.
If contract payment milestones or specific procedural clauses dictate that payment would only become payable at a later time, the government is not penalized with interest during the intervening period. Once that later due date arrives, the unpaid amount begins accumulating interest continuously until payment is made. Estimators and project teams reviewing potential disputes should assess the underlying schedule of values and contract payment provisions to pinpoint which date legally governs.
Checklist Item: Applying Simple Interest and Treasury Rates Across 6-Month Periods
A key financial aspect of interest recovery on federal claims is the calculation method and the applicable interest rate structure. Under FAR 33.208 Interest on claims, the government pays simple interest rather than compound interest. This simple interest is calculated at the rate fixed by the Secretary of the Treasury pursuant to the Disputes statute.
The statutory rate structure follows a semiannual adjustment schedule rather than remaining locked at a single figure:
- The initial interest rate is fixed by the Secretary of the Treasury for the period during which the contracting officer receives the contractor claim.
- The rate then adjusts to match the rate applicable for each 6-month period as fixed by the Treasury Secretary throughout the pendency of the claim.
- The simple interest calculation applies across these fluctuating semiannual rates until the final date of payment.
It is also worth noting that reciprocal interest mechanisms exist within federal contracting. The clause at 52.232-17 addresses the right of the government to collect interest on its own claims against a contractor, establishing parallel standards when funds are owed back to the agency.
Checklist Item: Protecting Accrual During Defective Certifications
Certification requirements are among the most scrutinized aspects of federal claim submission. When submitting larger adjustments, contractors must ensure compliance with statutory certification rules. A technical error or administrative flaw in a certificate could theoretically jeopardize the contractor's claim timeline. However, FAR 33.208 contains specific protections regarding defective certifications.
Under the regulation, interest on claims with defective certifications continues to be paid from the date that the contracting officer initially receives the claim. This rule protects contractors from forfeiting accumulated interest simply because a certification required correction or clarification. Rather than restarting the clock when a revised certificate is delivered, the initial receipt date preserves the interest accrual timeline while procedural matters are resolved.
Action Checklist for Estimators and Trade Contractors
To preserve your company's rights to statutory interest when preparing requests for equitable adjustments or formal claims, implement this procedural checklist:
- Establish whether your dispute qualifies as a formal claim rather than an uncertified change request when pricing change orders for extra work.
- Ensure complete compliance with certification mandates by reviewing guidelines on certifying a contract claim when required under subsection 33.207(a).
- Obtain written confirmation and transmission logs verifying the exact date the contracting officer receives the claim package.
- Evaluate contract terms to confirm whether payment otherwise would be due on a later date that could alter the interest starting point.
- Track semiannual Treasury rate changes for each 6-month period while the claim proceeds through evaluation or dispute resolution.
- Retain thorough submission records to demonstrate initial receipt if certification issues arise.
Sources
Published October 31, 2026. No affiliate links on this page. Facts come from the sources linked above; check them for updates.