Final notice for an unpaid invoice: template and when to send it

Send a final notice when the reminders have run out

A final notice comes after your reminders, not instead of them. Reminders ask the client for a payment date or a reply. A final notice asks for payment by a date you set and says what you will do if it does not arrive. So it is worth sending only once the gentler messages have had their chance: the past-due reminder emails that come before it have gone unanswered, or have been answered with dates that came and went.

Before you send one, rule out the two situations where a final notice is the wrong message:

• The invoice is stuck, not refused. A missing purchase order number, the wrong legal entity or a portal that rejected the upload can stop an invoice inside a client's accounts payable system without anyone telling you. Ask accounts payable for the status of the invoice by number first. Invoice payment terms: examples and wording lists the usual causes.
• The client has raised a problem. If they have disputed the work or the amount, answer that first. A deadline on a disputed invoice turns a disagreement into a standoff.

We suggest sending the notice a few working days after the last reminder, so the client has had a chance to answer that one. That is our advice, not a rule. If the date in the notice passes without payment, what to do when a client won't pay covers the steps after it.

Final notice invoice template: the email

Copy it and replace everything in square brackets. If the client has paid nothing, the invoice total and the amount outstanding are the same figure. Delete the optional line unless your signed agreement sets a late fee.

Subject: Final notice: invoice [Invoice number], [Amount outstanding] due by [Pay-by date]

Hi [Client contact name],

This is a final notice for invoice [Invoice number], which [Your business name] sent on [Invoice date] for [Invoice total]. Under our [Payment terms] terms it was due on [Original due date], and today it is [Days overdue] days overdue. We sent reminders on [Dates of earlier reminders], and the invoice is still unpaid.

Please pay the outstanding balance of [Amount outstanding] by [Pay-by date].

You can pay by:
[How to pay: bank transfer details, payment link, check address]

You can view and download the invoice here: [Invoice link]

If payment has not reached us by [Pay-by date], we will [Next step and the date you will take it].

[Optional, delete unless your signed agreement sets a late fee] Under our agreement, a late fee of [rate and basis, as the agreement words it] applies. If the invoice is paid on [Pay-by date], the fee is [fee in dollars] and the total is [total in dollars].

If something is holding up payment, such as a question about the invoice, the work or the timing, reply before [Pay-by date] and we will work it out with you, including a payment plan if that helps. If you have already paid, send me the payment reference and I will close this off.

[Your name]
[Your title], [Your business name]
[Your email] | [Your phone]

The next-step line matters more than any other. Write the one step you have actually decided on, with its date. For example:

• pause further work on the project from [date], as our agreement allows
• send a formal demand letter on [date]
• file a claim in small claims court after [date]
• refer the account to a collection agency on [date]

Pause work only if your agreement gives you that right. Each of these steps, and when it fits, is set out in what to do when a client won't pay.

Final notice letter for an overdue invoice

Send a letter as well as the email when you want a paper record, when emails have gone unanswered, or when your agreement says notices go by post. USPS Certified Mail proves you mailed it and shows when it was delivered or when delivery was attempted. Adding Return Receipt gets you a delivery record with the signature of the person who accepted it (USPS, checked on 28 October 2026). Keep the receipt with your copy of the letter.

[Your business name]
[Your address]
[Your email] | [Your phone]

[Date]

[Client contact name]
[Client company]
[Client address]

Sent by email and by Certified Mail, Return Receipt Requested [optional line]

Re: Final notice for invoice [Invoice number], [Amount outstanding] overdue

Dear [Client contact name],

On [Invoice date], [Your business name] issued invoice [Invoice number] to [Client company] for [Invoice total], on [Payment terms] terms. Payment was due on [Original due date]. As of the date of this letter, the invoice is [Days overdue] days overdue. We sent reminders on [Dates of earlier reminders], and the balance has not been paid.

Please pay the outstanding balance of [Amount outstanding] by [Pay-by date], using any of these:

[How to pay: bank transfer details, payment link, check address]

A copy of the invoice is enclosed. You can also view it at [Invoice link].

If full payment has not reached us by [Pay-by date], we will [Next step and the date you will take it].

[Optional, delete unless your signed agreement sets a late fee] Under our agreement, a late fee of [rate and basis, as the agreement words it] applies. If the invoice is paid on [Pay-by date], the fee is [fee in dollars] and the total due is [total in dollars].

If there is a reason this invoice has not been paid, including any concern about the work or the invoice itself, please contact me before [Pay-by date] at [Your email] or [Your phone] so that we can resolve it. If you have paid since our last reminder, please send the payment reference and disregard this letter.

Sincerely,

[Your name]
[Your title], [Your business name]

Enclosure: invoice [Invoice number]

How to write a final notice for payment: what to include

A final notice works when the client can act on it without having to ask you anything. This is our checklist, and each item is on it for that reason.

1. "Final notice" in the subject line and the first sentence, next to the invoice number, so it is not read as one more reminder.
2. The invoice number, its date and its total. Accounts payable finds invoices by number.
3. The payment terms and the original due date, such as "net 30, due Thursday 1 October 2026". If you only have the terms, the net terms calculator gives the date.
4. The amount outstanding today. If the client has paid part of it, ask for the balance, not the original total.
5. How many days overdue it is on the day you send it, counting from the day after the due date.
6. The reminders already sent, with their dates. They show the notice is not the first the client has heard of it.
7. A pay-by date written as a calendar date, not "within 14 days". A number of days leaves room to argue about when the count started.
8. How to pay, with the exact amount: bank details, a check address, a payment link, and a link to the invoice itself. If your payment link does not carry the amount, the notice has to.
9. What happens if the date passes: one step you will take, and when you will take it.
10. A late fee only if the signed agreement has one, stated in dollars rather than as a vague mention of "fees". The late fee calculator works out what a clause comes to.
11. A named person and a direct way to reply, with an open invitation to raise a dispute or propose a payment plan before the date.
12. A record. Attach or link the invoice, keep a copy of exactly what you sent, and note the date and how you sent it.

Set the pay-by date as a day on the calendar

We know of no rule that makes one period standard for a final notice on a business invoice. Unless your agreement sets a notice period, the date is generally yours to choose, so choose it on purpose.

Some state laws do give weight to the time after you present a claim. In Texas, for example, a claimant represented by a lawyer can recover attorney's fees on a claim for services or under a contract only if the claim was presented to the other side and the amount owed was not paid within 30 days after that (Tex. Civ. Prac. & Rem. Code 38.001 and 38.002, checked on 28 October 2026). If you may go to court, check the rules where you would file before you set the date.

Our suggestions:

• Long enough for one payment run. If the client pays suppliers in batches, the date has to leave room for one approval and one payment run. If you do not know when the next run is, ask accounts payable.
• Short enough to read as a deadline. A date two months away reads as one more reminder.
• A weekday that is not a public holiday. Check the date against the federal holiday list as well as the weekend. State holidays can differ from the federal list: California's state holidays, for example, include 31 March and the day after Thanksgiving (CalHR, checked on 28 October 2026). If the client's office keeps a state calendar, check that too. The net terms calculator flags a weekend but does not know public holidays.
• Before any legal deadline. If the time limit for bringing a claim could be close, do not let the notice window run past it.

A 14-day window has one practical advantage: it ends on the same weekday the notice went out. That makes it convenient, not standard.

One overdue invoice, worked from its date to the deadline

Here is the whole timeline for one example invoice: INV-0142 for $3,600.00, dated Tuesday 1 September 2026 on net 30 terms and emailed that day. Every date was computed with the code behind the net terms calculator and RunwayDue's reminder schedule, using the default Standard schedule with weekends skipped. The final notice goes out three days after the last reminder and gives 14 days to pay.

Three things in that table are easy to get wrong:

• The 30-day reminder went out at 32 days. Day 30 was Saturday 31 October, and reminders skip weekends, so it went on Monday 2 November by UTC dates, which in New York is about 7 pm on Sunday 1 November. Count days overdue on the day you actually send.
• A federal holiday falls inside the window. Veterans Day, Wednesday 11 November 2026, is on the federal holiday list (OPM, checked on 28 October 2026). It does not move a Thursday deadline, but it is one working day fewer for a client whose office observes it.
• Other windows land badly. Ten days from the notice is Sunday 15 November, so, following the weekday advice above, you would move it to Monday 16 November. Twenty-one days is Thursday 26 November 2026, which is Thanksgiving Day.

Filled in for this invoice, the heart of the email reads:

This is a final notice for invoice INV-0142, which [Your business name] sent on Tuesday 1 September 2026 for $3,600.00. Under our net 30 terms it was due on Thursday 1 October 2026, and today it is 35 days overdue. We sent reminders on 28 September, 1 October, 8 October, 15 October and 2 November, and the invoice is still unpaid.
Please pay the outstanding balance of $3,600.00 by Thursday 19 November 2026.

If, and only if, the signed agreement had a late fee of 1.5% a month charged by the day (the late fee calculator's own illustration, not a standard rate), the fee would be $62.14 on the day the notice went out and $86.99 on the pay-by date, so the optional line would ask for $3,686.99 in total by Thursday 19 November 2026.

What not to put in a final notice

The sentences to watch in a final notice are the ones that promise more than you will do, or claim more than you have.

• A step you will not take. If you write that you will file a claim on 20 November and you do not, the client learns that your dates move. Name only the step you have decided on. For debt collectors collecting consumer debts this is also the law (next section), and the FTC has said that a false threat of legal action by a business collecting its own consumer debts likely breaks the FTC Act as well. Whoever the client is, it is also about being believed.
• Arrest, jail or seized property. Do not suggest that not paying will lead to any of them. Where the federal debt collection rules apply, implying it is barred unless the action is lawful and actually intended.
• A borrowed voice. Do not make the letter look like a court or government document, and do not suggest a lawyer wrote it if none did.
• A fee the agreement never mentioned. A late fee generally has to come from an agreement the client accepted, such as the contract they signed before the work started. Treat one that appears for the first time in a final notice as a request: it is not something the client agreed to. Interest can differ: the late fee calculator page lists cases where a statute supplies it.
• An audience. Send it to your contact and, if they handle the invoice, the client's accounts payable team. Do not copy in people who have no part in paying it, and do not discuss the debt in public.
• An apology, or anger. "Sorry to chase" makes the deadline sound optional. An angry line gives the client something to answer other than the invoice.

Federal debt collection rules mostly cover consumer debts, not your invoice to a company

Each source in this section was checked on 28 October 2026.

The federal Fair Debt Collection Practices Act applies to a "debt" in its own narrow sense: money a natural person owes from a transaction that was primarily for personal, family or household purposes (15 U.S.C. 1692a(3) and (5)). An invoice to a company, or to a person buying your services for their business, is not that kind of debt.

The Act's rules also bind "debt collectors": businesses whose principal purpose is collecting debts, and anyone who regularly collects debts owed to someone else. A business collecting its own debts in its own name is generally not one. It becomes one if it collects under a different name that suggests a third party is collecting (1692a(6)). So a final notice you send in your own name, for your own invoice, to a business client generally falls outside the Act.

Where the Act does apply, for example when a private individual owes you for something bought for personal use and you pass the account to a collection agency, the collector must not use false, deceptive or misleading means. The listed examples include threatening action that cannot legally be taken or is not intended to be taken, implying that nonpayment will lead to arrest or the seizure of property unless that is lawful and intended, falsely implying that a communication is from a lawyer, and letters made to look as if they come from a court or government agency (15 U.S.C. 1692e(3), (4), (5) and (9)). The FTC publishes the Act's text as a convenience copy, where these are sections 803 and 807.

Outside the Act is not the same as anything goes. The FTC has said that even where the Act does not apply, collection is still covered by the FTC Act's ban on deceptive or unfair practices, that false threats of legal action likely break it, and that it has acted against creditors collecting their own debts for telling other people about a debt (FTC Business Blog, 8 December 2015). The post is written about debts owed by consumers and does not discuss business clients.

State law can reach further. California's Rosenthal Fair Debt Collection Practices Act counts as a debt collector anyone who, in the ordinary course of business, regularly collects covered debts on their own behalf or for others (Cal. Civ. Code 1788.2(c)). It requires every debt collector collecting a consumer debt to follow the federal rules in 15 U.S.C. 1692b to 1692j, which include the bar on empty threats (Cal. Civ. Code 1788.17). So in California, a business that regularly bills individuals for personal or household services, on credit, may be held to those rules when it chases them itself. The current text of section 1788.2, in force since 1 January 2026, also covers some commercial debts owed by individuals, but only to lenders, commercial financing providers and debt buyers, and it expressly leaves out trade credit: credit extended by a business whose main business is providing goods or services, in connection with providing them (1788.2(n) and (p)). An invoice for your services to a company is outside that extension. Other states have collection laws of their own, so if your client is an individual, check the rules that apply where you and they are.

Whatever rules apply, our advice is the same: write only what is true, and name only a step you will actually take. This is not legal advice; our editorial standards explain how the legal statements on this site are sourced and dated.

RunwayDue sends the reminders before the notice, and you send the notice

RunwayDue does not write or send a final notice. What it can automate is the run-up. Automatic reminders are part of Pro, at $15 a month billed annually or $17 month to month, and of the 14-day Pro trial every new account starts with. They are off until you switch them on. The default Standard schedule sends one 3 days before the due date, one on it, then 7, 14 and 30 days after, with weekends skipped and at most six per invoice unless you change the cap. Days and weekends follow UTC dates, so in the US each reminder usually arrives in the afternoon or evening of the day before. The built-in wording firms up as the invoice gets later but never sets a deadline or names a consequence: from 22 to 45 days overdue it asks for a reply, and after that for a payment date. The final notice is the step past that line, so you send it by hand.

On Free there are no automatic reminders, but an overdue invoice's page has "Email a reminder", which opens a short form and, when you press "Send reminder", sends the reminder wording for that many days overdue. Following up an invoice you already sent never uses one of Free's 5 invoices a month.

When the reminders have run out:

1. See which invoices need a notice. On Pro, the aged receivables report lists every unpaid invoice in columns for not yet due, 1 to 30, 31 to 60, 61 to 90 and over 90 days past the due date. On the Standard schedule the last reminder is due 30 days late, so the 31 to 60 column is the one to read. The example invoice moved into it on Sunday 1 November 2026, and its 30-day reminder went the next day.
2. Take the dates from the invoice's History. It lists each reminder sent, with its date and time, which is what the notice's reminder line needs. History gives them in UTC, so in the US an automatic reminder usually reached the client in the afternoon or evening of the day before the date History shows, as the example's 30-day reminder did. If the client may check the notice against their inbox, give the dates they will see there.
3. Copy the invoice's link. "Copy link" on the invoice's page gives a private link the client can open to view and print the invoice without logging in.
4. Send the notice from your own email. "Send the invoice again" on an overdue invoice does take a note, but that email's subject names the invoice and, after the greeting, it says "Here is invoice...", which is not how a final notice should read.
5. Pause the automatic reminders on that invoice. "Pause reminders for this invoice" on its page means no automatic reminder for that invoice goes out while the notice's deadline runs, and the pause is logged in its History. Reminders on the client's other invoices carry on unless you pause those too. On the Standard schedule nothing is left after the 30-day reminder anyway, but a longer schedule can still have one to come. The Persistent preset has eight steps, ending at 45 days, but the default cap of six applies to it too, so an invoice that gets every earlier step never reaches the last two unless you raise the cap to 8. With the cap raised, it would send the example invoice its 45-day reminder on Monday 16 November 2026, asking for a payment date three days before the notice's deadline.
6. Record the payment when it lands. If you have added a payment link in Settings, the client's copy of an unpaid invoice shows a Pay now button. It is one link for every invoice, so it does not carry the amount, which is why the notice should. A payment made through it does not mark the invoice paid by itself.

Frequently asked questions

How long should a final notice give the client to pay?

We know of no rule that sets a standard period, so unless your agreement sets one, pick a calendar date rather than a number of days. Some state laws give weight to the time after you present a claim (in Texas, 30 days matters for recovering attorney's fees), so if you may go to court, check the rules where you would file. Make it a weekday that is not a public holiday, long enough for one approval and payment run, and short enough to read as a deadline. Our example notice, sent on Thursday 5 November 2026, gives 14 days, to Thursday 19 November 2026, with Veterans Day inside the window.

Should a final notice go by email or by letter?

Either can work, and you can send both. Email is fast and dated. A letter sent by USPS Certified Mail proves you mailed it and shows when it was delivered or that delivery was attempted, and adding Return Receipt gets you the signature of whoever accepted it. In California, the courts' small claims guide says you must ask for the money before filing a case (unless there is a restraining order or asking would be dangerous), and a letter or an email can do that (checked on 28 October 2026).

Does the Fair Debt Collection Practices Act apply to a final notice?

Generally not when you chase your own invoice, in your own name, from a business client. The Act covers debts people owe for personal, family or household purposes, and mainly binds collectors collecting for others (15 U.S.C. 1692a). It can apply to a collection agency you pass the account to when the client is an individual who bought for personal, family or household use, and to you if you collect such a debt under a name that suggests someone else is collecting. In California, a business that regularly collects its own consumer debts may be held to similar rules.

Can a final notice add a late fee?

Generally only one the client already agreed to. Treat a late fee that first appears in a final notice as a request rather than something the client agreed to. Interest can be different. A few cases run on statute rather than contract, such as a federal agency client under the Prompt Payment Act, and some states supply a rate where none was agreed; the late fee calculator page lists examples with their sources. If your agreement has a clause, state the fee in dollars as of the pay-by date. RunwayDue never adds a late fee or interest to an invoice.

Will RunwayDue send the final notice for me?

No. RunwayDue's automatic reminders, part of Pro and the 14-day Pro trial, cover the messages before it: by default 3 days before the due date, on it, then 7, 14 and 30 days after. Their built-in wording never sets a deadline or names a consequence. You send the final notice yourself, from your own email with the invoice's private link, and pause that invoice's automatic reminders when you do.