Why This Matters More Than You Think
A late fee clause does two things: it compensates you for the cost of delayed payment, and — more importantly — it creates a financial incentive for the client to pay on time. Without a late fee, a client who pays 60 days late faces no consequence. With one, every day of delay costs money.
But late fee laws vary significantly by state. What's enforceable in Texas may not be enforceable in California. And the difference between a well-drafted late fee clause and a poorly drafted one can mean the difference between collecting your fee and having a court throw it out.
The General Rules
Before diving into state specifics, here are the principles that apply almost everywhere:
1. Contractual late fees must be reasonable
Courts distinguish between liquidated damages (a reasonable pre-estimate of the harm caused by late payment) and penalties (an amount designed to punish the debtor). Liquidated damages are enforceable; penalties are not.
Rates of 1–2% per month are almost universally upheld as reasonable for commercial invoices. Rates above 3% per month are increasingly likely to be challenged.
2. The fee should be in the contract
A late fee clause in your written agreement is far easier to enforce than one you add after the fact. The client must have agreed to the fee before the work began.
3. Without a contract, statutory interest applies
Even without a written agreement, most states provide for prejudgment interest — a statutory rate that accrues on unpaid debts from the date they become due. These rates are set by state law and range from about 4% to 12% per year.
4. Consumer vs. commercial rules differ
This article covers commercial (business-to-business) late fees. Consumer lending and consumer transactions are governed by different rules (Truth in Lending Act, state usury laws) that impose stricter limits.
State-by-State Statutory Interest Rates
When no contractual late fee rate is specified, these are the prejudgment interest rates that apply by default:
| State | Statutory Rate | Notes | |---|---|---| | Alabama | 6% per year | | | Alaska | 10.5% per year | Based on federal funds rate | | Arizona | 10% per year | | | Arkansas | 6% per year | Constitutional cap | | California | 10% per year for contracts; 7% without | [Cal. Civ. Code § 3289](https://leginfo.legislature.ca.gov/) | | Colorado | 8% per year | | | Connecticut | 10% per year | | | Delaware | 5% over Federal Reserve rate | | | Florida | 12% per year | Can be set by contract up to 18% (non-usurious for commercial) | | Georgia | 7% per year | | | Hawaii | 10% per year | | | Idaho | 12% per year | Highest flat statutory rate | | Illinois | 5% per year | | | Indiana | 8% per year | | | Iowa | 5% per year | | | Kansas | 10% per year | | | Kentucky | 8% per year | | | Louisiana | Judicial interest rate (set annually) | Approximately 4–6% | | Maine | Variable (set annually) | | | Maryland | 6% per year | | | Massachusetts | 12% per year | One of the highest | | Michigan | 5% per year | | | Minnesota | 10% per year | | | Mississippi | 8% per year | | | Missouri | 9% per year | | | Montana | 10% per year | | | Nebraska | 12% per year | | | Nevada | Prime rate + 2% | | | New Hampshire | 10% per year | | | New Jersey | Court rule rate (currently ~3–6%) | | | New Mexico | 15% per year | Highest statutory rate | | New York | 9% per year | [CPLR § 5004](https://www.nysenate.gov/legislation/laws/CVP/5004) | | North Carolina | 8% per year | | | North Dakota | 6% per year | | | Ohio | Varies (set by tax commissioner) | | | Oklahoma | 6% per year | | | Oregon | 9% per year | | | Pennsylvania | 6% per year | | | Rhode Island | 12% per year | | | South Carolina | 8.75% per year | | | South Dakota | 12% per year | | | Tennessee | 10% per year | | | Texas | 6% per year (10% on commercial transactions with agreement) | | | Utah | 10% per year | | | Vermont | 12% per year | | | Virginia | 6% per year | | | Washington | 12% per year | | | West Virginia | 7% per year | | | Wisconsin | 5% per year | | | Wyoming | 7% per year | |
*Note: Rates can change annually in some states. Always verify the current rate with your state's judiciary or a local attorney. For a regularly updated reference, see [PaidNice's state-by-state guide](https://www.paidnice.com/blog/late-fee-laws-by-all-us-states).*
Prompt Payment Acts: Extra Protection in Some States
Several states have Prompt Payment Acts that impose specific penalties for late payment on certain types of contracts:
Federal Government
The [Federal Prompt Payment Act](https://fiscal.treasury.gov/prompt-payment/) requires federal agencies to pay invoices on time or pay interest at a rate set semi-annually by the Treasury (currently 4.125% for January–June 2026).
California
The [California Prompt Payment Act](https://baylegal.com/california-prompt-payment-act-deadlines-penalties-and-your-rights/) requires property owners to pay contractors within 30 days of an approved payment request. Wrongful withholding is penalized at 2% per month on the amount withheld.
Illinois
The [Illinois Contractor Prompt Payment Act](https://thecromeenslawfirm.com/illinois-contractor-prompt-payment-act-overview/) requires payment within 15 days of an approved request. Interest accrues at 1% per month for prime contractors and 2% per month for subcontractors.
New York
New York's Prompt Payment Act applies to state agency contracts, requiring payment within 30 days and imposing interest for late payments.
How to Draft an Enforceable Late Fee Clause
Here's a clause designed to withstand legal challenge:
> Invoices are due within [14/30] days of the invoice date. Invoices not paid by the due date will accrue a late fee of [1.5]% per month ([18]% per annum) on the outstanding balance, beginning the first day after the due date. Both parties acknowledge that this rate represents a reasonable estimate of the damages incurred by Contractor due to late payment, including but not limited to lost opportunity costs, administrative costs of collection, and the time value of money. This rate shall not be construed as a penalty.
Why each element matters:
- "Reasonable estimate of damages" — This tracks the legal test for liquidated damages. Courts uphold fees that are reasonable pre-estimates; they strike down fees that are punitive.
- "Including but not limited to..." — This identifies specific categories of harm, showing the fee is grounded in actual economic impact.
- "Shall not be construed as a penalty" — An explicit statement that isn't dispositive (courts will look at the substance), but signals intent and is commonly included.
What Happens If You Don't Have a Late Fee Clause
Without a contractual late fee, you can still recover interest on unpaid invoices:
- Statutory prejudgment interest — Most states automatically award interest at the statutory rate from the date the debt became due. You don't need a contract to claim this.
- Post-judgment interest — After you win in court, the judgment accrues interest at the applicable rate (often the statutory rate) until paid.
- Freelancer protection laws — In [New York](https://dol.ny.gov/freelance-isnt-free-act), [California](https://www.zarmoney.com/blog/new-rights-for-freelancers-in-california-illinois-and-new-york), and Illinois, the freelancer protection statutes provide double or triple damages that dwarf any late fee you could charge.
Practical Tips
Don't get too aggressive with the rate
A 1.5% monthly rate (18% annualized) is the sweet spot — high enough to motivate timely payment, low enough to be clearly enforceable. Courts in some states have upheld rates up to 2% per month, but higher rates invite challenges.
Start charging immediately
Your clause should specify that fees begin accruing "the first day after the due date" — not after a grace period. Grace periods signal that the real deadline is later than the invoice date.
Include the clause in every invoice
Even if it's in your contract, print the late fee terms on every invoice as a reminder: "A late fee of 1.5% per month will be applied to overdue balances per our agreement."
Apply the fees consistently
If you waive late fees for one client, it weakens your ability to enforce them against another. Apply your late fee policy consistently, though you can choose to waive fees as a gesture of goodwill on a case-by-case basis (just don't make it the default).
Frequently Asked Questions
Can I charge late fees on invoices for work done without a written contract?
Not as a contractual late fee — that requires a written agreement. However, you can claim statutory prejudgment interest in most states, which doesn't require a contract.
Are late fees on invoices considered "interest" under usury laws?
Generally, usury laws apply to loans, not to late fees on commercial invoices for services rendered. However, if a court determines that your late fee is excessive, it may analyze it under the same principles that govern usurious interest. Keep your rate at or below 2% per month to stay safe.
What if the client disputes the work — can I still charge late fees?
If the dispute is legitimate and raised before the invoice was due, late fees may be paused during the dispute resolution process. If the dispute is raised only after the invoice is overdue (a common stalling tactic), courts typically allow late fees to continue accruing.
Can I add a late fee to an existing contract?
You can propose an amendment to the contract, but both parties must agree. You cannot unilaterally add a late fee clause to an existing agreement. For future projects, include the clause from the start.