Payment Reminder Generator

Enter the due date and this picks the stage the debt has reached, writes the message for it, and dates the rest of the ladder. Change the tone if you want; the stage is chosen by the calendar.

Rules differ by country. This tool performs the calculation you ask for. What you are entitled to charge, and how it must be presented, is set by your contract and your local law — check both before relying on a figure here.

What this tool does

The variable that matters when chasing an invoice is not the wording, it is the age. A message that is right on day three is limp on day forty-five, and the same message sent twice at day forty-five teaches the customer that nothing follows — which is the single most expensive thing a chaser sequence can communicate. So this tool takes the due date first and offers the tone second.

Six stages, from a note before the invoice falls due to a final notice. Each one carries the channel that suits it, because what changes with age is usually who you are writing to and how, not how sternly you write. A month of unanswered emails to the same contact is a signal to change the recipient, not the adjectives.

The cadence table is the half that gets skipped and the half that works. Every stage is dated from the due date, so the next step is already decided and nobody has to summon the will to make it in the moment. Escalating on a schedule is what separates a business with a collections process from one that sends a polite email and hopes.

Nothing here asserts an entitlement to interest or recovery costs. Whether your terms carry a late payment charge — and whether it is enforceable — depends on the contract and the country, so the fee sentence only appears if you switch it on.

How it works

  1. The calendar picks the stage

    Days between the due date and today decide which rung of the ladder you are on: advance notice before the date, then due today, first reminder to day 13, second to day 29, escalation to day 59, and final notice beyond that. You can override it, but the default is what the arithmetic says.

  2. Tone is a separate dial

    Friendly, firm and formal are the same stage said three ways — they do not skip rungs. A friendly final notice still says it is the last one; a formal first reminder still assumes an oversight. Mixing the two axes is how people end up sending a legal-sounding letter about an invoice that is four days late.

  3. The facts are filled in, not written

    Invoice number, amount, due date and the exact age go into both the subject line and the body. A chaser that says "the outstanding invoice" is asking the reader to go and find it; one with the number in the subject can be forwarded to accounts payable without being opened.

  4. The ladder gets dates

    Every stage is placed against the due date — three days before, on the day, day 3, day 14, day 30, day 60 — so the whole sequence exists before you need any of it. Each row also carries the non-message step that belongs at that age, from checking the invoice reached accounts payable to deciding whether to refer the debt.

Worked example

A £1,250 invoice was due on 1 March 2026. It is now 20 March and two emails have gone unanswered.

Inputs

Due date
1 March 2026
Today
20 March 2026
Age
19 days overdue
Tone
Firm

Result

Stage selected
Second reminder
Subject
Second reminder — invoice INV-2026-0042, 19 days overdue
Channel
Email plus a phone call
Also do
Send a statement of account showing every open invoice
Next step falls due
31 March 2026 — escalation

Why it matters: Nineteen days is where a missed invoice and a customer with a cash-flow problem stop looking the same. The message stops asking and starts requiring a date — and the escalation is already booked for the 31st, so the decision to make it has been taken in advance.

Best practices

  • Put the invoice number and the amount in the subject line. Chasers get forwarded internally far more often than they get replied to, and the subject is the only part that always survives.
  • Send the advance notice. A note three days before the due date costs nothing and catches the largest category of late invoices — the ones nobody refused, just missed.
  • Change the channel before you change the vocabulary. Two weeks of silence over email means email is not working; a phone call at day 14 outperforms a stronger email at day 21.
  • Attach a fresh copy of the invoice from the first reminder onward. "We never received it" is the most common reply, and it is answered by the attachment, not by the message.
  • Escalate to a different reader, not just a different tone. At a month, ask who owns the payment internally — you are usually writing to someone who cannot release it.
  • Only send a final notice you intend to follow. A final notice followed by another final notice is the clearest possible signal that nothing happens next.

Common mistakes

Sending the same message repeatedly

A sequence where message three reads like message one tells the customer the process has no end state. Payers with limited cash pay the supplier whose next step is visible, and identical reminders make yours invisible.

Opening with an apology

"Sorry to chase, I know you're busy" concedes that asking to be paid is an imposition. It is not an imposition, and the phrasing invites the reply that the payer is indeed busy. Be courteous, not apologetic.

Threatening a charge the terms do not carry

Naming a late payment charge that your contract never mentioned is the fastest way to lose the argument, because it hands the customer a reason to dispute the whole invoice rather than pay it. Check your terms first — that is why the charge sentence here is switched off by default.

Waiting for a better moment

The next reminder always feels premature and then, a week later, overdue. Fixing the dates against the due date removes the judgement call entirely, which is the only reliable way to keep sending them.

Frequently asked questions

How soon after the due date should I send the first reminder?

Around three days. Same-day chasing catches payments already in transit and reads as impatient; a week is long enough for the invoice to fall out of the current payment run, which can cost you a full cycle. Three days is late enough to be sure and early enough to still make the run.

How many reminders before I escalate?

Two unanswered messages is the signal, not a number of days. If nobody has replied twice, the problem is the recipient rather than the message, and the next one should go to a different person — a finance lead, a director, or whoever owns the supplier relationship.

Should reminders be email, phone or letter?

Email early, phone in the middle, and both plus a posted letter at the end. Email is free and forwardable, which is exactly what you want while this is still administrative. A phone call gets a commitment from a human, which is what you want once it is not.

Can I charge interest on a late invoice?

It depends entirely on your contract and your jurisdiction — several countries also provide a statutory route for commercial debts. Because it varies, this tool never asserts the charge: switch the sentence on only if your own terms actually provide for one, and work out the figure with the late fee calculator.

When should I stop chasing?

When you have named a final step and are ready to take it. That point is a business decision — referral to a collections agency, a formal claim, or writing the balance off — and the cost of each is worth comparing against the debt before you send the notice that promises one.

Turn the answer into an invoice

The result above transfers straight into the invoice generator — dates, amounts and terms already filled in. Free, no account needed.

Open the invoice generator

Sources & further reading

Related

Invoice types

Published · General information, not legal, tax or financial advice.