The short answer
First, switch on the free reminders already built into your invoicing tool (Xero sends them 7, 14 and 21 days after the due date by default). If you want firmer, more personal follow-ups, a daily Make scenario finds overdue invoices, asks AI to write a reminder in the right tone for how late it is, and saves it as a Gmail draft for you to send. For business clients, the final reminder can mention statutory late payment interest and compensation.
- Who it’s for
- UK freelancers, consultants and small agencies who invoice businesses
- Time to set up
- 5 minutes (built-in reminders) + 45 minutes (AI follow-ups)
- Difficulty
- Beginner
- Monthly cost
- £0–£11
What does this automation do?
It makes sure no invoice is forgotten, and that the follow-ups get firmer at the right pace without you writing awkward emails. It comes in two layers:
- Built-in reminders (5 minutes, free): your invoicing tool emails the client automatically when an invoice is overdue.
- AI follow-ups (45 minutes, free on Make): a daily check that drafts personal, escalating reminders, with UK late payment rights in the final one, ready for you to send.
What do you need before you start?
- Your invoicing tool: Xero, Stripe Invoicing, QuickBooks, FreeAgent or a Google Sheet
- A free Make account for the AI layer
- Gmail or Outlook
How do I set it up?
Step 1: Switch on your invoicing tool’s built-in reminders
In Xero, go to Sales › Invoices, open Invoice reminders, tick the option to email customers when an invoice is overdue, and save. Xero sets three reminders by default, at 7, 14 and 21 days after the due date, and you can edit the wording or add up to five. Reminders only go to sent, unpaid invoices with a contact email, and they stop once the payment is reconciled, so keep your bank feed up to date. Stripe, QuickBooks and FreeAgent have similar settings.
If that’s all you need, stop here.
Step 2: Decide your escalation ladder
A typical ladder for business clients:
| Days overdue | Tone | Content |
|---|---|---|
| 3 | Friendly nudge | “Just checking this reached the right person”, invoice link |
| 14 | Clear and direct | Amount, original due date, payment link, ask for a payment date |
| 30 | Firm | Statement of the debt, mention of statutory interest and compensation, date you’ll call |
Step 3: Build a daily Make scenario that finds overdue invoices
Create a scenario, set the schedule to every day at 9:00, and add your invoicing tool’s search module (e.g. Xero › Search invoices / List invoices) filtered to sales invoices that are authorised (sent) and unpaid with a due date before today.
Step 4: Work out how many days overdue each invoice is
Add a Set variable step with Make’s date functions to calculate days overdue, then a filter that only lets through invoices at exactly 3, 14 or 30 days. That way each invoice gets one email per stage, not one a day.
Step 5: Ask AI to write the reminder in the right tone
Add an AI module (OpenAI › Generate a response, or Make’s built-in AI) with the prompt below, mapping client name, invoice number, amount, due date, days overdue, project name and payment link.
Step 6: Save it as a draft (or send) and log it
Add Gmail › Create a draft (or the Microsoft 365 equivalent) addressed to the client. Optionally add a note to the invoice’s history or a Google Sheet log so you can see what was sent.
Step 7: Review for a fortnight, then decide whether to auto-send
Check each draft for the first two weeks. Look out for invoices paid by a route your tool hasn’t reconciled yet. Once you trust it, you can switch the 3-day nudge to Send an email and keep the firmer stages as drafts.
The copy-paste prompt
Write a payment reminder email from [YOUR NAME], [BUSINESS NAME].
Client contact: {{contact_first_name}} at {{client_company}}.
Invoice {{invoice_number}} for £{{amount_due}}, due {{due_date}},
now {{days_overdue}} days overdue. Project: {{reference}}.
Payment link: {{online_invoice_url}}. Bank details: [SORT CODE / ACCOUNT].
Tone by stage:
- 3 days: friendly, assume it was missed, 60 words max.
- 14 days: clear and direct, ask them to confirm a payment date, 90 words max.
- 30 days: firm and professional. State that under the Late Payment of
Commercial Debts (Interest) Act 1998 we are entitled to claim statutory
interest (8% above the Bank of England base rate) and fixed compensation,
and that we will add these if payment isn't received by [DATE = today + 7].
120 words max. Only include this paragraph if the client is a business.
Rules: British English. No threats beyond the stated next step. No guilt-tripping.
Include the invoice number and amount in the first sentence.
Subject line on the first line, starting "Subject:".Make template outline
| # | Module | Notes |
|---|---|---|
| 1 | Scheduler | Daily, 9:00 |
| 2 | Xero › Search/List invoices (or Stripe, or Google Sheets › Search rows) | Sales invoices, authorised, amount due > 0, due date < today |
| 3 | Tools › Set variable | days_overdue = today − due date, in days |
| 4 | Filter | days_overdue is 3, 14 or 30 |
| 5 | OpenAI › Generate a response (or Make AI) | Prompt above |
| 6 | Gmail › Create a draft | To the invoice contact; subject from the first line |
| 7 | Google Sheets › Add a row (optional) | Log: date, invoice, stage |
What UK rules apply?
- Statutory interest (business clients only). You can claim 8% a year above the Bank of England base rate on late business-to-business payments (GOV.UK). Check the current Bank Rate; the rate that applies is the one in force on 30 June or 31 December before the debt became overdue.
- Fixed compensation. £40 for debts under £1,000, £70 for £1,000 to £9,999.99, and £100 for £10,000 or more, plus reasonable extra recovery costs (GOV.UK).
- When is it “late”? After the agreed payment date, or 30 days after the client received the invoice (or the work) if you didn’t agree one.
- Consumers are different. None of the above applies to invoices to private individuals. Remove the 30-day paragraph for them.
- Data. Client contact details pass through Make and your AI provider; keep prompts to the minimum needed (no bank statements, no personal notes).
What can go wrong?
- Chasing paid invoices. The classic embarrassment. Reconcile your bank feed daily, or add a check against a “paid” column before drafting.
- Wrong contact. Invoices sometimes go to a person who has left. If a client doesn’t respond to the 3-day nudge, check who should receive invoices.
- Too many emails. The exact-day filter in Step 4 prevents daily repeats; don’t replace it with “greater than”.
- Legal overreach. Don’t threaten court action or credit reporting in an automated email. If it gets to that point, it needs a human (and possibly legal advice).
Frequently asked questions
Can I charge interest on late invoices in the UK?
For business-to-business invoices, yes. Under the Late Payment of Commercial Debts (Interest) Act 1998 you can claim interest at 8% above the Bank of England base rate, plus fixed compensation of £40, £70 or £100 depending on the debt size, unless your contract sets a different substantial remedy. It doesn’t apply to invoices to consumers.
Are Xero’s built-in reminders enough?
For many freelancers, yes. They stop automatically once the invoice is paid and reconciled. The AI layer is worth it when you want reminders that reference the project, escalate in tone, and are reviewed by you before sending.
Will automated reminders annoy good clients?
A polite reminder a week after the due date is normal practice. Keep the first one friendly, include the invoice and a payment link, and pause the automation for clients you’re talking to directly.
Should the AI send reminders on its own?
Start with drafts so you can see the tone and catch mistakes, such as chasing an invoice the client already paid by bank transfer. After a couple of weeks of clean drafts, many people switch the first friendly reminder to auto-send and keep later ones as drafts.
I use Stripe or a spreadsheet, not Xero. Does this still work?
Yes. Stripe Invoicing has its own reminder settings and a Make app, and a Google Sheet with due date, amount and paid status works as the source too. Swap the first module and keep the rest.
Sources
- Xero Central: Get your invoices paid faster (invoice reminders)
- GOV.UK: Interest on late commercial payments
- GOV.UK: Claim debt recovery costs on late payments
- Bank of England: Bank Rate
- Make pricing
This guide is general information, not legal, tax or financial advice. Tool prices and screens change; we re-check every guide regularly. Spotted something out of date? Tell us and we’ll fix it.