Federal Judgment Interest Calculator
Estimate post-judgment interest under 28 U.S.C. Section 1961 using a clean, attorney-ready workflow. Enter the judgment amount, annual federal interest rate, judgment date, and payment date to calculate accrued interest, total payoff, elapsed days, and a visual balance growth chart.
Calculate Federal Judgment Interest
This calculator applies an annual rate to a federal judgment from the date of entry through the payment date, with daily accrual and annual compounding for a practical Section 1961 estimate.
Results
Your estimate will appear here
Enter the judgment details and click Calculate Interest to generate a payoff estimate and chart.
Expert Guide to Using a Federal Judgment Interest Calculator
A federal judgment interest calculator helps lawyers, financial professionals, creditors, and judgment debtors estimate how much post-judgment interest accrues after a federal court enters a money judgment. In federal practice, post-judgment interest is generally governed by 28 U.S.C. Section 1961. While the statute sounds simple at first glance, users often need clarity on what rate applies, when interest begins, how compounding works, and how to produce a reasonable payoff estimate for settlement, collection, accounting, or litigation planning.
This page is designed to give you both a working calculator and a practical legal-financial overview. The calculator above focuses on the most common use case: estimating post-judgment interest based on a principal amount, an annual federal rate, the date judgment was entered, and the date payment will be made. The result can help you prepare demand letters, evaluate settlement timing, compare collection options, or cross-check a payoff statement.
What is federal judgment interest?
Federal judgment interest, often called post-judgment interest, is the interest that accrues on a money judgment after it is entered in federal court. The core purpose is straightforward: it compensates the prevailing party for the time value of money between entry of judgment and actual payment. If a debtor does not pay immediately, the balance does not stay static. Instead, interest continues to accrue, increasing the amount required to fully satisfy the judgment.
Under Section 1961, the applicable rate is tied to the weekly average 1-year constant maturity Treasury yield for the calendar week preceding the date of judgment. That means the rate is not negotiated between the parties after judgment and is not usually based on a bank lending rate. It is a federally defined benchmark linked to Treasury market data.
Why this calculator matters in practice
Even modest rates can produce meaningful dollar amounts on large judgments. A business judgment of $500,000 at a 5.00% annual rate adds roughly $25,000 over one year before considering compounding structure. For institutional litigants, insurers, and high-value commercial disputes, the cost of delay can materially influence post-trial strategy. For individuals and smaller businesses, understanding interest can prevent underpayment or overpayment when trying to close a case.
- Creditors use the calculation to estimate the amount due on a target payment date.
- Debtors use it to evaluate how delay affects total exposure.
- Attorneys use it when drafting payoff demands, motions, settlement communications, and judgments.
- Accountants and finance teams use it to book receivables, reserves, or settlement liabilities.
How federal post-judgment interest is generally calculated
In broad terms, the formula begins with the judgment principal, applies the statutory annual rate, accrues interest from the judgment date, and compounds annually. In practical terms, a useful estimate often follows these steps:
- Determine the original money judgment amount.
- Identify the correct Section 1961 annual interest rate in effect for the relevant week.
- Count the number of days from the judgment date to the payoff date.
- Apply daily accrual.
- Compound annually for each completed year after entry.
- Add the accrued interest to the principal to estimate the payoff total.
The calculator on this page uses a practical implementation of that method. It computes full-year annual compounding and then calculates the remaining partial-year daily accrual on the updated balance. It also gives you a simple interest option for comparison, which can be useful for internal modeling or for checking whether another payoff statement appears to have omitted compounding.
Key inputs you need before calculating
To use a federal judgment interest calculator correctly, gather the following:
- Judgment amount: the principal sum awarded by the court.
- Judgment date: usually the date the clerk entered the money judgment.
- Payment date: the expected date of full payment or satisfaction.
- Applicable annual rate: the weekly average 1-year constant maturity Treasury yield for the calendar week preceding the judgment date.
If there have been partial payments, amended judgments, fee awards added later, or appellate modifications, the calculation may need to be segmented into multiple periods. In those situations, a single-line estimate is not always enough. You may need a transaction-level payoff schedule that restarts accrual on revised balances.
Real rate context: recent 1-year Treasury yield environment
Because Section 1961 is tied to Treasury yields, the federal judgment interest rate changes over time with market conditions. The table below shows approximate ranges for the 1-year Treasury environment in recent years, illustrating why post-judgment interest can vary significantly depending on when judgment was entered.
| Period | Approximate 1-Year Treasury Yield Environment | Practical Impact on Judgments |
|---|---|---|
| 2020 | Often below 0.20% | Very low carrying cost on delayed payment compared with later years. |
| 2021 | Frequently around 0.05% to 0.15% | Post-judgment interest remained minimal on many federal judgments. |
| 2022 | Rose sharply, often above 4.00% by year end | Delay became more expensive, especially in larger commercial disputes. |
| 2023 | Often around 4.70% to 5.40% | Judgment balances grew materially if unpaid for many months. |
| 2024 | Commonly in the mid-4% to low-5% range | Payoff estimates remained highly sensitive to timing and delay. |
These figures are contextual and not a substitute for pulling the exact weekly average applicable to a specific judgment date. The main takeaway is that federal judgment interest is not static. A judgment entered in a near-zero rate environment can produce very different accrual than one entered when Treasury yields are above 5%.
Simple interest vs annual compounding
One of the most common misunderstandings is whether federal judgment interest is simple interest. For many federal judgments, Section 1961 is understood to require annual compounding. That matters because the balance used to calculate interest can increase at each yearly anniversary of the judgment. The effect is often modest over short periods but becomes increasingly important over multi-year collection efforts.
| Scenario | Principal | Annual Rate | Approximate 3-Year Interest | Observation |
|---|---|---|---|---|
| Simple Interest | $100,000 | 5.00% | $15,000 | Interest stays linear over time. |
| Annual Compounding | $100,000 | 5.00% | About $15,763 | Each completed year increases the base for the next year. |
| Difference | $100,000 | 5.00% | About $763 | The gap grows with time and larger balances. |
Common issues that affect accuracy
A calculator is only as accurate as the inputs and assumptions behind it. These issues frequently affect federal payoff calculations:
- Wrong rate source: users sometimes plug in a state court rate, contract rate, or prime rate instead of the federal statutory Treasury-based rate.
- Wrong start date: interest generally runs from the date of entry of judgment, not necessarily the date of verdict, order, or demand.
- Partial payments: if the debtor makes interim payments, interest should usually be recalculated on the reduced principal going forward.
- Amended judgments: fee awards, costs, or remittitur can change the amount on which interest accrues.
- Appeals: appellate proceedings may raise timing and scope questions, especially where the judgment is modified.
- Taxable costs and attorney fees: whether they accrue interest and from what date can depend on how and when they were reduced to judgment.
When to use a calculator and when to go deeper
This tool is ideal when you need a fast estimate for a single judgment amount over a continuous date range. It is well suited for:
- Settlement planning
- Demand letters
- Collection forecasting
- Client reporting
- Reserve and accrual estimates
- Checking a payoff quote for reasonableness
You may need a more tailored analysis if the case includes multiple judgments, partial satisfactions, post-judgment fees added later, or mixed federal and state law issues. In complex litigation, counsel often prepares a ledger-style calculation that tracks each event date, principal adjustment, and interest period separately.
Authoritative sources for federal judgment interest
If you want to verify the legal framework or obtain the applicable Treasury data, start with these sources:
- Cornell Law School Legal Information Institute: 28 U.S.C. Section 1961
- U.S. Department of the Treasury
- Board of Governors of the Federal Reserve System
For many legal teams, the best workflow is to confirm the judgment date, pull the relevant Treasury yield data for the preceding calendar week, save the source to the file, and then run the calculation. That creates a stronger record if the payoff amount is later challenged.
Best practices for attorneys and finance teams
- Save a copy of the judgment and docket entry showing the date of entry.
- Document the exact Treasury rate used and the source from which it was obtained.
- State clearly whether your estimate assumes simple interest or annual compounding.
- Recalculate whenever the expected payment date changes.
- If partial payments occur, update the principal balance immediately.
- Use a ledger or spreadsheet for multi-event cases instead of relying on a single-period estimate.
Final takeaway
A federal judgment interest calculator is one of the most practical tools in post-judgment administration. When used correctly, it turns abstract statutory language into a concrete dollar figure that can drive negotiation, payment, and compliance. The most important variables are the right federal rate, the correct judgment date, and an accurate treatment of time and compounding. With those in place, you can quickly estimate the current payoff amount and understand how much delay is costing on a daily basis.
Use the calculator above for a fast estimate, then verify the rate and any case-specific nuances before relying on the final number in formal correspondence, court filings, or financial reporting.