The On-Time Invoice Kit: Milestone Invoice + 3 Reminder Emails

Late pay is normal. Chasing it doesn't have to be.

If a client has paid you late, you're not alone. In the Remote Contractor Management Report 2025, 85% of freelancers said they get paid late at least some of the time, and just over 21% get paid late (or not at all) more often than on time.

Bonsai looked at about 3 years of invoices from more than 100,000 freelancers. 29% of invoices were paid late. Their data also shows which invoices go late: big ones, crypto ones, and ones nobody follows up on. Each of those has a simple fix, and that's what this kit is built on.

Fix 01: Split big invoices into milestones

One big invoice at the end is the riskiest way to get paid. You do all the work first, then wait. And Bonsai's data says the bigger the invoice, the more likely it's late: invoices over $20,000 were 3x more likely to be paid late than invoices under $100.

Milestones fix both problems. You get money before you start, the client pays smaller amounts that are easier to approve, and if a payment stalls, you find out early instead of at the very end.

Check the math: 3 × $8,000 = $24,000. Each invoice is also under the $20,000 line where Bonsai saw late payments jump. Equal thirds are just the simple version. Some people bill 50% upfront and 50% on delivery, or 40/30/30. The key is: never do all the work before the first payment.

Fix 02: Short terms, due date on line 1

Short terms help, but they don't fix everything. In Xero's research on about 10 million invoices from 150,000+ small businesses (summary here), businesses with one-week terms still waited 15 days on average to get paid. So pick short terms and make the due date impossible to miss.

• Line 1 of the invoice is the due date, written as a real date: "Due: Monday, November 9, 2026". Not "Net 7" alone. Clients don't do date math.
• Put the same date in the email subject line.
• Use 7 days for most work. Whatever you pick, write it in the contract before work starts.
• Send the invoice the same day the milestone is reached. A late invoice is a late payment.

Fix 03: Get paid by bank or card, not crypto

Bonsai found that crypto payments were late almost 3x more often than ACH/bank payments. Make paying you the easiest thing the client does all day: put a Pay now link (card) and your bank details right on the invoice.

• Bank transfer (ACH or wire): cheap and normal for bigger invoices. Put the full details on the invoice so nobody has to email you for them.
• Card: fastest for the client. Tools like Stripe or PayPal add a pay button to your invoice. They charge a fee, so you can price it in.
• Crypto: only if the client insists, and never as your only option.

Fix 04: Remind BEFORE the due date

Most people send their first reminder after the invoice is already late. By then, the client's payment run may have passed. A friendly note 3 days before the due date (a common rule) catches problems early: wrong email, missing PO number, the person who approves is on holiday.

1. 3 days before the due date: friendly heads-up (Email 1).
2. On the due date: short "due today" note (Email 2).
3. 7 days after the due date: firm but polite, mentions the pause rule (Email 3).
4. 14 days after the due date: work pauses until it's paid, as written in your contract.

The milestone invoice template

Copy this into Google Docs, your invoicing tool or an email. Replace everything in [brackets]. Note the order: due date and amount first, details after.

DUE: [Day, Month Date, Year]  |  AMOUNT DUE: $[amount]

INVOICE #[number]  |  Milestone [1] of [3]: [Start / Midpoint / Delivery]
Issued: [date]  |  Terms: [7] days

From: [Your name / business], [email]
To: [Client company], [contact name], [PO number if they use one]

Project: [project name]
Total project price: $[total]

This invoice:
- Milestone [1]: [what is included, e.g. kickoff + first draft] ... $[amount]

Paid so far: $[0]
Left after this invoice: $[remaining]

HOW TO PAY (pick one):
1) Card: [Pay now link]
2) Bank transfer: [Bank name] | Account name: [name] | Account no: [number] | Routing/SWIFT: [code]
Please add invoice #[number] as the payment reference.

Note: if this invoice is unpaid 14 days after the due date, work pauses until it is paid, as agreed in our contract.

Thank you!

Worked example: the $24,000 project

Example dates only (2026), all Mondays except Email 1, which goes out the Friday before. Reminders are Email 1 (3 days before), Email 2 (due date) and Email 3 (7 days after). Set all the reminders the day you send the invoice, so you never have to remember.

The 3 reminder emails

Subject: Invoice #[number] due [Monday, Nov 9]: quick heads-up

Hi [Name],

Quick heads-up: invoice #[number] for $[amount] ([milestone name]) is due this [Monday, Nov 9].

You can pay by card here: [Pay now link]
Or by bank transfer (details are on the invoice, attached again).

If anything is missing on your side, like a PO number or a different billing email, just reply and I'll fix it today.

Thanks!
[Your name]

Subject: Invoice #[number] is due today ($[amount])

Hi [Name],

Just a reminder that invoice #[number] for $[amount] is due today, [Monday, Nov 9].

Pay by card: [Pay now link]
Bank details are on the attached invoice.

If it's already on its way, thank you, and please ignore this.

[Your name]

Subject: Invoice #[number] is 7 days overdue

Hi [Name],

Invoice #[number] for $[amount] was due on [Monday, Nov 9] and is now 7 days overdue.

Could you let me know when it will be paid? Here's the link again: [Pay now link] (bank details attached).

As agreed in our contract, if it's still unpaid on [Monday, Nov 23] (14 days after the due date), I'll pause work on [project] until it's settled. I'd much rather keep going, so if there's a problem on your side, reply and we'll sort it out.

Thanks,
[Your name]

Put the rules in your contract first

The invoice and reminders work best when the client already agreed to the rules. Add these lines to your contract or proposal before work starts:

Payment terms:
- The project price of $[total] is billed in [3] milestones: [start], [midpoint] and [delivery], $[amount] each.
- Each invoice is due [7] days after it is sent.
- Payment by bank transfer or card. [No crypto / Crypto only by written agreement.]
- If an invoice is unpaid 14 days after its due date, work pauses until it is paid. Deadlines move by the length of the pause.

Problem finder

Common mistakes

• Doing all the work before the first invoice.
• Writing "Net 7" instead of a real due date.
• Sending the invoice days after the milestone.
• Waiting until it's late to send the first reminder.
• Threatening a pause that's not in the contract. Agree on it first, then it's just the rule.

Let Claude fill in the kit for you

Help me set up on-time invoicing for a client project.

Project: [what I'm doing]
Client: [company], contact [name]
Total price: $[total]
Start date: [date] | Expected delivery: [date]
Payment terms: [7] days | Payment: bank transfer + card

Please:
1) Split the price into milestones (start, midpoint, delivery). Show the math.
2) Give me the dates: each invoice date, due date, a reminder 3 days before, a note on the due date, a reminder 7 days after, and the date work pauses (14 days after due).
3) Write the 3 invoices with the due date and amount on line 1.
4) Write the 3 reminder emails for milestone 1. Friendly, short, plain English, with the real dates filled in.

Links and tools

Quick answers

Isn't it rude to remind someone before the invoice is due?

No. A friendly heads-up 3 days early reads as organized, not pushy. It also catches problems (wrong email, missing PO) while there's still time to pay on time.

What if the client says no to milestones?

Offer two milestones instead of three, like 50% upfront and 50% on delivery. If they won't pay anything before you start, that tells you something about how the final invoice will go.

Do I really have to pause work at day 14?

It's your call. It's a common rule, not a law. But only use it if it's in your contract, and always tell the client the date in advance (Email 3 does that).

Which payment terms should I use?

7 days is a good start for most freelance work. Xero's research shows even one-week terms often stretch, so the reminders matter as much as the terms.