How to write a demand letter that actually gets paid.

CPLR § 5004 · CPLR § 213(2)

What a demand letter is, and what it is not.

A demand letter states that someone owes you something, explains why, says how much, sets a date, and tells them what happens if the date passes. That is the whole form. It is not a lawsuit, it does not require any particular format, and it has no magic words. Its power comes from three places: it forces the other side to take a position in writing, it creates a dated record you can show a judge, and it signals that you know what your claim is worth and intend to pursue it.

It is also, often, the last step before a filing, and the letter should be written with that in mind. Every sentence should be one you would be comfortable having an arbitrator in small claims read aloud. That one rule eliminates most of the mistakes people make.

The seven parts.

1. The facts. Dates, amounts, names, and what happened, in order, without adjectives. Who agreed to what, when the money changed hands or the work was done, when payment was due, what was paid, what was not. If there is a document, name it and attach it. If there are messages, quote the important ones with their dates. A reader who knows nothing should finish this section understanding exactly what went wrong.

2. The legal basis. One or two sentences on why the other side owes you. Often it is simply breach of contract: you agreed, you performed, they did not pay. Sometimes a statute does the work, and in New York several statutes do a lot of work; those are below. You do not need case citations. You need the right label for the claim and, where one exists, the section of the statute.

3. The amount. A single number, with the arithmetic shown. Principal owed, less what was paid, plus any interest or statutory additions you are entitled to, each on its own line. A letter that says you owe me a lot of money is ignored. A letter that says $2,400 principal, plus $189 interest at nine percent from March 1, 2026, total $2,589 is taken seriously because it reads like a claim that has already been drafted for court.

4. The deadline. A specific date, not a number of days, so there is no argument about when the clock started. Ten to fourteen days from the date the letter will arrive is standard. Shorter reads as a bluff; longer invites delay.

5. The consequence. What you will do if the deadline passes, stated once and plainly. For most claims that is a small claims filing, or a filing in the appropriate court, and a request for statutory interest and costs. Name the court if you know it. Do not list five things you might do. Say the one thing you will do.

6. The delivery method. How the letter is being sent, stated in the letter itself: by certified mail, return receipt requested, and by email to the address you have used with this person. Recording the method in the text means the copy you keep proves the method by itself.

7. The tone. Flat. Factual. Not friendly, not angry. The letter should read as though it was written by someone who is not emotional about the outcome because the outcome is not in doubt. Every insult you leave out makes the letter stronger.

New York hooks that change the number.

A demand letter in New York can often demand more than the principal, and a letter that knows this is harder to ignore.

• Nine percent interest. CPLR § 5004 sets New York's statutory interest rate at nine percent per year, and on a contract claim interest runs from the date of breach. On a $5,000 debt that is $450 a year, and a letter that states it is reminding the other side that waiting costs them money.
• Double damages for freelancers. New York's Freelance Isn't Free Act lets a freelancer who was not paid on time recover double the unpaid amount, plus attorney's fees, and applies statewide. A demand letter that cites the Act is demanding twice the invoice. Start at the Freelance Isn't Free Act.
• Up to double the security deposit. General Obligations Law § 7-108 requires a landlord to return a deposit within 14 days with an itemized statement, and a willful violation can cost the landlord up to twice the deposit.
• Wage claims. Labor Law § 198 allows an employee who was not paid wages to recover liquidated damages equal to the unpaid wages, plus interest and attorney's fees. See unpaid wages.
• Consumer deception. A business that deceived a consumer can face statutory minimum damages and fees under General Business Law § 349, which is the hook for the letters on vendors who kept a deposit.

Cite these only if they apply, and only if you are certain of the section. A letter that cites the wrong statute is worse than one that cites none, because it tells the other side you do not know your claim. If you are unsure, describe the rule in words.

How to send it so it counts.

Send it two ways: certified mail with return receipt, and email. The certified mail creates a Postal Service record of mailing and, if signed for, of delivery; the email gets it read the same day. Keep the receipt, the tracking number, and a PDF of the letter exactly as sent. If you are sending to a business, send to its registered address on file with the Department of State as well as to the place you dealt with. A refused or unclaimed certified letter is not a problem for you; the attempt is the record. The full mechanics are on how to send a demand letter in New York.

What not to write.

Three things appear in DIY letters constantly and each one damages the letter.

Threats of criminal prosecution as leverage. Do not write that you will go to the police, the district attorney, or a licensing board unless they pay. Using the threat of criminal charges or a professional complaint to extract money in a civil dispute is improper; for a lawyer it is a disciplinary violation, and for anyone it can expose the writer to a claim of coercion or extortion. If a crime was committed, report it. Do not trade it.

Exaggerated claims. Demanding $10,000 on a $2,400 debt, adding emotional distress to an invoice dispute, or threatening a lawsuit in federal court over a security deposit. Inflated letters get ignored because the other side correctly concludes the writer does not know what the claim is worth.

Insults, history, and ultimatums about the relationship. The letter is not the place to explain how disappointed you are. Every sentence about feelings is a sentence the other side can point to as evidence this is personal rather than legal.

We walk through the three most common structural mistakes, with a worked example, on a demand letter sample outline for New York.

A short outline you can follow.

Open with your name and address, the date, the recipient's name and address, and a subject line that names the claim and the amount: demand for payment of $2,400 invoice dated January 15, 2026. In the first paragraph, say in one sentence what this letter is: a formal demand for payment of the amount below by the stated date.

In the next two or three paragraphs, state the facts in date order with the documents named. Then one paragraph on the legal basis: the agreement, the breach, and any statute that applies. Then the amount, itemized, with interest computed to a specific date. Then the deadline as a date. Then the consequence, one sentence. Then a sentence stating how the letter is being delivered. Then a closing line that leaves the door open: payment can be made by the following methods; contact me in writing with any questions. Sign it. Attach the key documents and list them as enclosures.

One page is ideal. Two is acceptable. Three means you are arguing instead of demanding.

When a DIY letter is enough, and what the letter does either way.

Write it yourself when the amount is small relative to a flat fee, the facts are simple, the other side is an individual who will recognize your name, and you are willing to follow through in small claims. Most personal loans between friends, roommate debts, and small refund disputes fall here. Our guides on lending money that was not repaid and the New York small claims court guide were written for exactly that reader.

Attorney letterhead changes the math when the other side is a business with a lawyer or an insurer, when a statute adds damages or fees that you need stated precisely, when the amount is large enough that a few percentage points of response rate matter, or when the other side has already ignored you. A letter from a law firm tells the recipient that someone who can file and litigate has reviewed the claim and put their name on it. That is not a guarantee of payment; nothing is. It is a different letter, and recipients treat it differently. The comparison is on attorney demand letter vs. writing it yourself, and what a flat fee covers is on flat-fee demand letters.

Whoever writes it, the letter does the same work. It converts a dispute that has been happening in texts and phone calls into a dated, written claim with a number and a deadline. It forces the other side to respond or to be silent, and either one helps you: a response commits them to a position, and silence is what you show the arbitrator when they later claim they would have paid if only someone had asked. And in a meaningful share of cases, it ends the dispute, because the recipient does the arithmetic on interest, costs, and a court date and decides that paying is cheaper.

When a letter is not the right tool: when the other side has no money and no prospects, when the claim is already past the six-year contract limitations period under CPLR § 213(2) with nothing to restart it, or when the dispute is genuinely about facts that only a hearing can resolve. In those cases a letter is a step you take for the record, not a solution, and you should know that going in. Demand letter vs. small claims covers the decision.

Read next.

• Demand letter sample outline for New York: a $2,400 invoice letter walked through sentence by sentence.
• How to send a demand letter in New York: certified mail, email, registered agents, refused letters.
• Attorney demand letter vs. writing it yourself: cost, credibility, and when a lawyer's letter is overkill.
• Unpaid invoices for small businesses: the most common demand letter we send.
• The Freelance Isn't Free Act: double damages for unpaid freelancers.
• A vendor kept your deposit: consumer refund demands.
• Lent money and not paid back: personal loan demands.
• NYC broker fees and the FARE Act: demanding an illegal fee back.