Automatic invoice payment reminders that stay polite (and get read)

Updated October 21, 2026 · App names checked against vendor documentation; vendors rename things, so search the step picker for the key word if a name differs.

Start with what you already have

Before building any automation, check your invoicing tool. QuickBooks Online, Stripe Invoicing, Xero and FreshBooks all include some form of automatic payment reminders in their settings. They're free with your plan, they know when an invoice is paid, and they stop on their own. Turn them on first.

Built-in reminders are often generic, though. If you want reminders that sound like you, escalate gently over time, or cover invoices from more than one system, a small automation helps.

The 3-step reminder sequence

A simple structure that works for most service businesses:

1. Day 0 (due date): a friendly heads-up. Assume good faith. Include the pay link.
2. Day 7: polite and direct. 'It still shows as open on our side — anything holding it up?' This invites the real reason (wrong address, approval stuck, card expired).
3. Day 14: firm but courteous. Ask them to reply with the date you can expect payment. A date is a commitment; 'soon' isn't.

After day 14, switch to a personal phone call for anything that matters. Automation is for the routine cases.

Build it in Zapier (QuickBooks Online example)

1. Trigger: QuickBooks Online › New Invoice Due, which has a days setting. Make one Zap with 0 days for the due-date reminder, and duplicate it for 7 and 14.
2. Search: QuickBooks Online › Find Invoice to get the current balance.
3. Filter by Zapier: continue only if the balance is greater than 0. This is the most important step — never remind someone who's already paid.
4. Optional: an AI step to adjust the wording to the stage and the client.
5. Action: Gmail › Send Email with the right template.

Using a spreadsheet instead of accounting software? Use Schedule by Zapier to run every morning and look up rows whose due date is today, 7 or 14 days ago and whose status isn't 'Paid'.

Build it in Make or n8n

In Make, schedule a scenario daily, search for unpaid invoices (QuickBooks or Google Sheets modules), and use a Router with three routes for each stage, each ending in Gmail › Send an email. In n8n, use a Schedule Trigger, the QuickBooks Online or Google Sheets node to get invoices, a filter for balance and dates, a Switch node by stage, and the Gmail node to send.

DAY 0 — Subject: Invoice {{Invoice Number}} is due today
Hi {{First Name}}, quick heads-up that invoice {{Invoice Number}} for {{Amount}} is due today. You can pay here: {{Pay Link}}. If it's already on its way, thank you — please ignore this.

DAY 7 — Subject: Following up on invoice {{Invoice Number}}
Hi {{First Name}}, invoice {{Invoice Number}} for {{Amount}} was due on {{Due Date}} and still shows as open on our side. Here's the link again: {{Pay Link}}. If something's holding it up — wrong amount, need a different payment method — just reply and I'll sort it.

DAY 14 — Subject: Invoice {{Invoice Number}} — can you confirm a payment date?
Hi {{First Name}}, I'm following up again on invoice {{Invoice Number}} for {{Amount}}, now two weeks past due. Could you reply with the date we can expect payment? Pay link: {{Pay Link}}. Thanks for sorting this out.

Tips that make reminders work better

• Make paying easy. Every reminder should have a one-click pay link. If the invoice needs a login to pay, expect delays.
• Send from a real person's address, and make sure replies reach someone.
• Set terms up front. 'Due in 14 days' on the proposal and invoice makes reminders feel like process, not pressure.
• Don't add threats or legal language in automated emails. If you charge late fees, state your policy clearly in your terms and keep it consistent; check what's allowed where you operate.
• Treat big clients differently. For your largest accounts, have the day 14 step create a draft or a task for you instead of sending automatically.

How to know it's working

Before you switch it on, write down your current average days-to-paid (most invoicing tools have an aged receivables or A/R report). Check the same number after a couple of months. That's the only honest measure of whether reminders are speeding up your cash flow.