The short answer
- Send the first reminder the day after the due date, not a week later - prompt chasers get paid first, and waiting signals the invoice does not matter.
- Put the invoice number and the amount in the subject line. The email should be findable in a search, not pretty.
- Say the number out loud in the first line: 'Invoice 14 for $600 was due on the 1st.' No wind-up, no 'just checking in'.
- Ask one clear question: has it been scheduled for payment? A yes or no is an answer; 'looking into it' is not.
- Stay neutral in tone. Anger feels justified and costs money; boredom is what gets accounts departments moving.
The three emails, in order
- Reminder one, day one past due: 'Hi - invoice 14 for $600 was due yesterday. Has it been scheduled? Happy to resend the invoice or a payment link if that helps.' Two sentences, one question.
- Reminder two, one week later: 'Following up on invoice 14 ($600, now 7 days past due). Can you confirm a payment date this week?' Same facts, firmer close.
- Reminder three, two weeks later, new subject line: 'Invoice 14 - $600, 21 days past due. I need a payment date by Friday, or I'll pause new work until it's settled.' This is the polite version of an ultimatum - and it must be true, so only write it if you mean it.
- After three: stop emailing weekly. Move to a phone call, a formal demand letter, or pause the work. More identical emails train them that nothing happens.
What makes reminders work
A reminder is a small system, not a confrontation. The freelancers who get paid fastest are rarely the most aggressive - they are the most predictable. Same day, same format, same question, every time. The client learns that an invoice from you comes with a rhythm, and that rhythm is harder to ignore than any tone of voice. Track three things per invoice: when it went out, when it was due, and what you did last. That is the whole machinery - and it is why the ageing column exists in every serious tracking sheet.
- One page with every invoice and its age - that list decides who you email today, not your mood.
- A fixed rhythm you can keep for months, because a system you abandon in week three protects nobody.
- A note of what each chase achieved, so the fourth email references the first three.
When it is not worth sending reminder four
- The client is more than 60 days late on two invoices - new work stops until the oldest one clears.
- They answered three reminders with no date - the next message is a letter, not an email.
- The amount is small enough that a formal chase costs more than the invoice - write it off, write it down, and stop working for them.
- They asked for a payment plan - that is a win, get it in writing with dates, and keep to it.
The free tool for this
Invoice total, with a discount and a tax rate - Invoice total, with a discount and a tax rate. It runs in the page, asks for your own numbers, and sends nothing anywhere.
If you would rather not build it yourself
ClientOS does the remembering: every invoice with an ageing column that tells you which reminder is due today, and a per-client roll-up so you know who to pause work for. The emails stay yours - the list that triggers them should not live in your head. ClientOS is $19. See it on the shop, and there is a plain page about it here: what it holds.
Questions people actually ask
Should I charge a late fee?
Only if your invoice said so before the work started. Adding one retroactively starts an argument that costs more than the fee. A late-fee term on the NEXT invoice with every new client works better than a fight over this one.
Is a reminder the day after the due date too pushy?
No - it is professional. Payment terms are a contract, and a prompt, polite question about them is normal business. Waiting two weeks teaches the client that your dates are decorations.
What if they say the invoice never arrived?
Resend it immediately and say 'no problem' - once. Keep the original send date in your records. If the same client 'never receives' invoices twice, send everything tracked or by a method that proves delivery.
Read next
How to keep track of unpaid invoices without a system you hate, What to look for in a client tracker before you pay for one, The client onboarding checklist that prevents every later argument, The one-page weekly review for a one-person business, What every invoice line item should say (and what never to write).