How to Invoice Someone Who's Slow to Pay (Templates)

How do you invoice someone who's slow to pay?

You follow up on a schedule: a friendly reminder the day after the due date, a firmer past-due notice about a week later, and a final notice around the 30-day mark that names what happens next. Resend the invoice PDF with every message; from an app like Voice Invoice, that's a minute's work. Keep the tone matter-of-fact: the work is done, and you're asking when it gets paid.

That's the whole system. Most slow payment isn't a client deciding not to pay you. It's an invoice in a spam folder, a missed check run, or an approval queue waiting on a PO number. Each rung of the ladder clears a different excuse, and a client who pays on the first reminder never meets the other two.

When should you follow up on an unpaid invoice?

First, normalize the problem: unpaid invoices are the ordinary condition of service work, not a sign you picked a bad client. In Intuit QuickBooks' 2025 US Small Business Late Payments Report, a January 2025 survey of 2,487 US small businesses, 47% of businesses had some invoices more than 30 days overdue, and businesses owed money were owed about $17,500 on average (QuickBooks, May 2025). The invoices that get paid are the ones somebody keeps in front of the client.

The ladder has four rungs, in this order:

1. Day after the due date: friendly reminder. Assumes it slipped. Asks for a payment date.
2. 7–14 days past due: past-due notice. States the facts plainly and asks for a date this week.
3. A phone call, if you can get one. Five minutes with a human clears approval queues that email never does.
4. Around 30 days past due: final notice. One deadline, one named next step. The last message you send.

Scale the ladder to the invoice. On a small Net 7 job for a homeowner, two rungs are enough: reminder on day 2, final notice at day 14. A corporate client's payment cycle runs monthly, so a past-due notice at day 8 can land before their check run even happens. One thing never changes: the due date goes on the invoice as an actual date, not just a term, so nobody spends the ladder arguing arithmetic (the invoice due-date calculator prints it for you).

What do you say in a friendly payment reminder?

Short, warm, and specific. The reminder's only jobs are to surface the invoice again and get a date: invoice number, amount, original due date, and one face-saving out, because the most common reason for slow payment really is a missed email. This one goes out September 2, the day after a $1,150 invoice came due:

"Could you confirm when it's scheduled to pay?" is the sentence that does the work. It asks for information, not money, and it gets a reply either way: a date, or the real blocker (a PO number, a vendor form, a dispute), which is what you want surfaced on day one. Swap in your own client, numbers, and dates; the shape is what matters.

What do you write in a past-due notice?

A week to ten days later, the past-due notice stops assuming the email got buried. It states the facts (invoice number, amount, how far past due) and asks for a commitment: a payment date this week. If you run a late-fee policy the client agreed to before the work, this is where one calm sentence acknowledges it. Same invoice, September 9:

The offer to fix something is not decoration: a meaningful share of slow payments are stuck on a PO number or an approval you can clear in ten minutes, and this is the cheapest moment to find out. Between this message and the final one, make the phone call. Five minutes of "when will this be paid?" from a human clears an approval queue faster than any email.

When do you send a final notice?

Around 30 days past due, or once the past-due notice and the phone call have both gone unanswered, whichever comes first. It reads differently from everything before it: short, formal, no warmth to misread, one deadline and one consequence. And the consequence has to be something you will actually do. Same invoice, October 1:

Two rules make it work. Name only a step you're genuinely prepared to take: small-claims court, a collection agency, or no further work until the balance clears are the standard options. An empty threat collected once is a threat you never have again. And send it once: if the deadline passes in silence, the next move is the one you named, or a deliberate decision to price the loss into your next quote for that client.

Should you resend the invoice with every reminder?

Yes. Every message carries the invoice PDF attached again. It closes off the most common low-drama explanation ("it never reached me"), hands the client's accounts-payable person a forwardable document, and means nobody has to ask you to resend before they can pay. An invoice that's trivial to pay gets paid.

This is where invoicing from your phone quietly pays off. Every invoice you've made in Voice Invoice lives on your device, so "send it again" is opening the invoice and tapping share: email, text, whatever channel the client actually reads. The whole cycle takes a minute from the truck, which means it happens on the day it should.

Need to send an invoice twice (or three times)? Voice Invoice keeps every PDF you've made on your phone, and resending takes about a minute. Free for 3 invoices a month.

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What do you do with a client who's always slow?

A client who pays 40 days late every single time isn't a follow-up problem anymore. They're a terms problem, and the fix happens on the next job, not the current invoice:

1. Shorten the terms. Due on receipt or Net 7 for repeat offenders; there's no award for offering a month of free credit to someone who takes two (which terms fit which clients).
2. Take a deposit. Half up front on the next job is a normal ask, and it converts their slowness into your working capital.
3. Apply the late-fee policy every time. If they agreed to 1.5% a month, the fee lands on past-due balances like clockwork: the client who's slow on purpose pays for the delay (the full late-fee playbook).
4. Price the delay in, or walk. If none of that changes anything, quote the next job knowing payment will lag, or decline politely. Capacity handed to a client who never pays on time is capacity a good client doesn't get.

Common mistakes

Mistake: Waiting until you're annoyed to say anything

The first contact at day 30 writes itself in a voice you don't want to send. Follow-ups written on schedule stay professional; follow-ups written on frustration don't. The day-after reminder takes two minutes precisely because nothing has gone wrong yet.

Mistake: Apologizing for asking

"Sorry to bother you" hands the invoice to the bottom of the pile. You finished the work and you're asking when it will be paid: polite and neutral, never sorry.

Mistake: Getting firmer without naming a consequence

Three messages that each say "please pay soon" are one message sent three times. Escalation is the deadline plus the named next step; anything louder with nothing new in it reads as noise the client can wait out.

Mistake: Introducing a late fee in a reminder

The fee has to come from a policy the client agreed to before the work and that appears on the invoice itself. A fee invented at reminder-time isn't enforceable, and it wrecks the tone of the whole ladder (how to set that up).

Mistake: Threatening what you won't do

"Our lawyers will be in touch" is a costly sentence if no lawyer exists. Whatever the final notice names, be ready to do it. Spend credibility once on a bluff and every future invoice from you is negotiable.

FAQ

How do you politely remind a client to pay an invoice?

Send a short note the day after the due date: name the invoice number, the amount, and the original due date, ask them to confirm when it's scheduled to pay, and attach the invoice again. One friendly paragraph is enough.

Is it rude to send a payment reminder?

No. A payment reminder is normal, professional bookkeeping: the client's own accounting process assumes vendors follow up. You finished the work; asking when it will be paid is not a favor you're requesting.

How many reminders should I send before giving up?

The standard ladder is three messages (a friendly reminder, a past-due notice, and a final notice with a deadline) plus a phone call between the second and third if you can get one. After the final notice's deadline passes, stop reminding and take the step you named, or consciously let it go. Reminders after a final notice just teach the client your deadlines are decorative.

What's the difference between a past-due notice and a final notice?

A past-due notice says "this invoice is overdue, so when can you pay?" and assumes good faith. A final notice says "pay by this date or this specific thing happens next" and is the last message you send. The difference is the named consequence and the deadline; without both, it's just a louder reminder.

Should I attach the invoice again to a payment reminder?

Yes, every time. It kills the "I never got it" explanation, gives the client's accounts-payable person a forwardable PDF, and means nobody has to dig through an inbox to pay you.

Can I charge a late fee on a slow-paying client?

Only if the client agreed to the fee before the work (in your contract, estimate, or written terms) and the policy appears on the invoice itself. The standard rate is 1.5% per month on the past-due balance after a grace period. Full rules and the exact policy line: how to charge late fees on an invoice.

Next step

The ladder works best when it's set up before anything is late: terms, the printed due date, and (if you use one) the late-fee policy on every invoice you send. Then a past-due follow-up is a two-minute message, not a dread project. To tighten up the document itself first, start here: How to Write an Invoice (With Examples).

Make the invoice easy to resend: create your first invoice by voice on iPhone in about a minute.

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