New Hampshire gives business invoices a 10% default rate, lets a written business agreement set any rate — even compounding — and runs small claims up to $10,000. The catch is time: you have just three years to sue on an unpaid invoice, shorter than most states. Here's what New Hampshire freelancers and small businesses need to know.
New Hampshire Late Fee Calculator
Quick estimate at the standard 1.5%/month rate — New Hampshire has no cap on a written business rate. For grace periods, flat fees, and a PDF invoice, use the full late fee calculator.
No Rate in the Contract? New Hampshire Gives Business Invoices 10%
Under RSA 336:1, I, the rate of interest on a business transaction is 10% a year unless the parties agreed otherwise in writing. Consumer credit transactions are carved out, so the 10% applies to invoices between businesses — which covers a freelancer billing a company. That's higher than Connecticut's 8% default, and in Maine an unpaid invoice gets no statutory rate at all until you serve a notice of claim.
Once a case is filed, a different clock takes over: prejudgment and judgment interest run at a floating rate set by the state treasurer each year — the 26-week Treasury bill rate plus 2 points (RSA 336:1, II). In a year when T-bills are near 4%, that's roughly 6%, which is lower than the 10% business rate. Another reason to write your own rate into the contract.
Is There a Cap on a Written Late Fee in New Hampshire?
Not for business transactions. RSA 336:1 doesn't just let you agree a different rate in writing — it expressly lets a written agreement on a business transaction provide for charges other than simple interest. That's unusual: in most states, compounding or a stacked fee structure is where trouble starts. In New Hampshire, a written business agreement can provide for it.
What that does and doesn't mean. The national-standard 1.5% a month (18% a year) is on solid ground with a business client. But "permitted by statute" isn't the same as "any number goes" — a charge that can only be read as punishment, especially one stated per day, can still be struck as a penalty. See is a daily late fee legal on an invoice, and if you're combining a flat fee with interest, can you charge a flat late fee and interest on the same invoice.
For individual clients buying for personal or household use, consumer credit rules apply instead — keep those clauses simple and modest.
Three Years to Sue — Shorter Than Most States
RSA 508:4 gives three years for most personal actions, including breach of contract, measured from the act or omission complained of. Most states give five or six years on a written contract. In New Hampshire, an invoice that went unpaid in early 2024 is close to the line by early 2027. If a client has stopped responding, decide early whether you'll pursue it.
New Hampshire Small Claims: $10,000
Small claims in New Hampshire is part of the District Division of the Circuit Court, with a ceiling of $10,000 excluding interest and costs (RSA 503:1). The District Division hears other civil cases up to $25,000; above that is Superior Court. Lawyers are allowed but not required, and most people file on their own. Is it worth suing a client over an unpaid invoice works through whether a claim is worth your hours.
How New Hampshire Compares to Its Neighbors
Scroll sideways to see all columns
| State | Rate rule | Small claims limit |
|---|---|---|
| New Hampshire | 10%/yr on business transactions unless agreed otherwise; no business cap | $10,000 |
| Maine | No general cap on a written B2B rate; no interest before a notice of claim without a contract rate | $10,000 (since Jan 2026) |
| Massachusetts | 12%/yr on contract judgments; no commercial ceiling below criminal usury | $7,000 |
| Connecticut | 8% default; 12% usury cap is for loans | $5,000 |
| New York | Contract-dependent; statewide Freelance Isn't Free Act | $10,000 in NYC, $5,000 elsewhere |
Southern New Hampshire freelancers often bill Boston-area clients. The trade-off: Massachusetts gives 12% on contract judgments and six years to sue, New Hampshire gives 10% on business invoices from day one but only three years. See the Massachusetts and Maine guides.
Setting Up Enforceable Late Fees in New Hampshire
- Write the rate into the contract — 1.5% a month is standard and uncapped for business transactions.
- If you want compounding or a combined flat fee + interest, say so in writing. RSA 336:1 permits it for business transactions, but only by written agreement.
- Put the rate and due date on every invoice, not only in the original agreement.
- Watch the three-year clock. Calendar a decision date for every invoice more than six months overdue.
Collecting in New Hampshire
- Small claims (Circuit Court, District Division): up to $10,000, excluding interest and costs (RSA 503:1)
- District Division civil cases: up to $25,000; Superior Court above that
- Default interest on a business transaction with no written rate: 10% a year (RSA 336:1, I)
- Judgment and prejudgment interest: 26-week Treasury bill rate + 2 points, reset annually (RSA 336:1, II)
- Statute of limitations: 3 years for most personal actions, including contract (RSA 508:4)
Need to calculate exactly what your New Hampshire client owes with late fees included? Get the updated total instantly.
Calculate Late Fees →New Hampshire is flexible on what you can charge a business client — 10% a year without a clause, any agreed rate with one, and even compounding if it's in writing. What it isn't flexible on is time: three years to sue is short. Write your terms down and don't let unpaid invoices drift.
Frequently Asked Questions
Is there a free New Hampshire late fee calculator? +
Yes. The quick calculator above estimates the fee at the common 1.5% a month. For grace periods, flat fees and a downloadable PDF, use GetSoloTools' full late fee calculator.
What interest applies in New Hampshire if my contract doesn't state a rate? +
For a business transaction, 10% a year under RSA 336:1, I, unless the parties agreed otherwise in writing. Consumer credit transactions are excluded from that rule. Once you sue, prejudgment and judgment interest run at a floating rate set each year: the 26-week Treasury bill rate plus 2 points (RSA 336:1, II).
Is there a cap on late fees in New Hampshire? +
Not for business transactions. RSA 336:1 lets the parties to a business transaction agree a different rate in writing, and even agree to charges other than simple interest, such as compounding. The common 1.5% a month is on solid ground with a business client. A charge large enough to read as a penalty, particularly one stated per day, can still be struck down.
What is the small claims limit in New Hampshire? +
$10,000, excluding interest and costs (RSA 503:1), in the District Division of the Circuit Court. The District Division hears other civil cases up to $25,000; above that, the Superior Court. Parties may be represented by a lawyer in small claims, though most people represent themselves.
How long do I have to sue for an unpaid invoice in New Hampshire? +
Three years. RSA 508:4 gives three years for most personal actions, including breach of contract, which is shorter than most states. Don't let an overdue invoice sit.