Wanting your clients to hear from you and not from a system is a reasonable thing to want, and a message that knows the account does tend to get a better reply. What makes it hard is arithmetic: businesses affected by late payment spend an average of 86 hours a year chasing it. Sorting those messages into the ones that need you and the ones that don't gives you most of that time back.
In this article
The short version
- Businesses affected by late payment spend an average of 86 hours a year chasing it, on Small Business Commissioner research.
- Most of those hours go on messages whose value is that they arrive at all, on the day.
- Independent research puts a reminder's worth at roughly 25 percent against sending nothing, and moving it earlier made businesses pay sooner without changing whether they paid, in work by Gillitzer and Sinning.
- What your clients notice is a message that knows their account and a reply that reaches a person who can act on it.
- Among repeat payers in Adfin's book, 27.4% were never late once, while the 24.3% who were late at least 80% of the time produced 51.9% of all late payments (Adfin platform data, 1,359 business-customer pairs with five or more payments).
The week this happens in
You've got thirty or forty invoices outstanding and you know almost every name on the list: the client who always pays on the 20th, the one who needs a purchase order number in the subject line, the one whose query from March nobody ever closed off.
On a good week you sit down with the ageing report open and write to all of them. On a normal week you get through the biggest six, and the rest wait for a week you never quite get. By then you're writing a first reminder on an invoice five weeks old, and it reads as an apology whatever words you use.
Chasing competes with client work, and client work has somebody waiting at the other end of it. The 86 hours a year in the government research is an average across affected businesses, roughly two working weeks spent asking for money you've already earned.
What your clients notice about a personal message
Two quite different things travel under the word "personal", and only one of them costs you your Monday.
One is that you typed it. Your client can't tell, and no research we could find measures what customers make of an AI-drafted reminder against a hand-written one, so a preference claimed either way is a guess. No UK legal duty to disclose AI drafting exists either, and should invoice reminders come from a person or an AI? has the professional position.
The other is that the message knows their account. It uses the invoice number they'd recognise, it doesn't ask for an invoice they paid last week, and a reply reaches somebody who can answer. Being treated like a client is that second version, and it survives being sent by software: what it needs is your ledger, your reply-to address and a named contact in the footer.
Sorting your chasing into two piles
Put each message from last quarter into one of two piles: the ones where your judgement was the value, and the ones where the value was that they went out at all.
| Message | Which pile | Why |
|---|---|---|
| The invoice, with terms and a payment link | Routine | The wording is settled and the timing is the due date |
| A note a few days before the due date | Routine | Its whole job is arriving before the money moves |
| First reminder the day after the due date | Routine | Factual, short, and better on the day than on the Friday |
| Second reminder a week over | Routine | Same message, a different channel if the first went unread |
| A statement where several invoices are open | Routine | One list of what's owed, sent on a rule you set |
| A reply to a query or a dispute | Yours | Whatever you say next either closes it or hardens it |
| A client who says cash is tight this month | Yours | An instalment arrangement is a negotiation |
| Anything naming interest, a fee or a consequence | Yours | Get the figure wrong and you've handed them an argument |
| Your largest client, at any stage | Yours | You're managing a relationship and a receivable together |
Most people find the routine pile far bigger than they expected, and the other one a handful of accounts.
Your own numbers tend to agree. Among repeat payers in Adfin's book, 27.4% were never late once, while the 24.3% who were late at least 80% of the time accounted for 51.9% of all late payments (Adfin platform data, 1,359 business-customer pairs with five or more customer-initiated payments). Those pairs qualified by paying five times and the book leans towards small accountancy practices, so read the shape and read it as these businesses. Your short list is usually shorter than it feels, and how to set different chasing rules for different clients covers treating those accounts differently.
Words for the messages that need you
Lines you can use as they stand. Telling a client what to expect, once:
- "From this month you'll get a reminder the day after an invoice is due, and a second a week later if it's still open. If anything looks wrong, reply to it and it comes straight to me."
Putting your name behind a scheduled message, in the sign-off:
- "Any queries on this, reply to this email or call me on [number] and I'll pick it up."
For the conversation a reminder can't have:
- "Invoice 1042 for £1,200 was due on the 30th and it's still open. Is something holding it up at your end?"
- "If this month is tight, I can split it over three payments starting on the 15th. Would that help?"
- "So it goes out in the run on the 14th. I'll note that, and I'll come back to you on the 15th if it hasn't landed."
And for a client you chase every month, where a better reminder isn't the useful change:
- "You're on our books for the same fee every month, so shall we set up a direct debit and stop us both doing this?"
More lines like these are collected in difficult payment conversations. The direct debit one is worth practising, because a client who agrees to a mandate needs none of the others again, and how to tell clients you're moving them to direct debit takes it from that one conversation to a whole client list.
What the routine messages need instead of you
A reminder's value doesn't rest on who typed it. In a field experiment on Australian business tax debts, a reminder letter raised the probability of payment by roughly 25 percent against sending nothing, and moving it earlier inside a three-week window prompted faster payment without changing whether payment arrived within seven weeks, in Gillitzer and Sinning's ANU working paper. Tax debts owed to a revenue authority, by letter, in 2018: the nearest independent evidence going, and not a study of your invoices.
What the routine pile does need is a payment route with nothing in the way, a cap on how often one client hears from you across every channel together, and a reply address reaching a human being.
Timing runs two questions together. Across all businesses and all customers, no reliable evidence settles a best channel or a best hour, so a page offering you Tuesday at 10am has invented it. For one of your clients, their own record answers something narrower: what they replied to before, and how quickly they paid. How does AI decide when to chase an invoice? has the mechanics.
Where the routine part can go
Handing it over means writing the rules of engagement down once: which channels are allowed, how persistent a sequence may be, what can leave without you seeing it, and which accounts you always want in front of you. Adfin's Customer Agents work a ledger inside limits like those, sending from your own email domain, alongside instalment plans, late fees, payment retries and a statement when an account goes quiet, with you approving whatever you've asked to approve.
What can be claimed here is capability. An agent can hold one client's pattern across four hundred accounts in a way you can across ten, and whether acting on that pattern collects money any sooner hasn't been measured by anybody, us included, so a vendor quoting you days-faster is ahead of the evidence. Can AI chase invoices for you? draws the boundary in detail.
What you keep is the part you wanted. The call where somebody explains they're in difficulty, the decision to wait a fortnight on a client worth waiting for, the query needing a proper answer: your judgement was always the personal part, and the typing was the tax on it.
Common questions
How do I keep chasing personal when I haven't got time for it? Split your messages into the ones where your judgement is the value and the ones where the value is that they went out on the day. The second group can be scheduled without your clients losing anything they'd notice, as long as the message is accurate about their account and a reply reaches a person.
Which payment reminders should come from me personally? Anything answering a query or a dispute, any negotiation over instalments, anything naming interest or a fee, and your largest accounts at any stage. A first reminder on a small undisputed invoice is the safest thing to schedule.
Does automated chasing damage client relationships? No research we could find measures how customers react to an automated reminder against a hand-written one, so nobody can tell you either way. What you control is that the message is accurate about the account, that its frequency is capped, and that replies reach somebody who can act.
What should I tell clients before scheduled reminders start? One line, once: when reminders arrive, how many there are, and who to reply to if an invoice looks wrong. Predictable chasing tends to be taken less personally than chasing arriving as a surprise.
Is there a best time of day to send a payment reminder? Across all businesses there's no reliable answer, and any specific hour offered without a method behind it is a guess. For one client, their own history of replies and payments is a real answer, and that narrower claim is the one worth acting on.
How much time does chasing invoices actually take? Government research puts it at an average of 86 hours a year for each business affected by late payment, or about two working weeks. Useful as a figure to measure your own against before you change anything.
Sources
- Small Business Commissioner — late payment research (accurate as of August 2026)
- Gillitzer and Sinning, ANU Tax and Transfer Policy Institute — nudging businesses to pay their taxes, does timing matter (accurate as of August 2026)
This article covers process and practice information and is not legal advice. If you're deciding how far to automate escalation, late fees or an account stop against an individual or a sole trader, that's a decision worth taking advice on. Last updated August 2026.
