First, don't take it personally
A client going quiet on an unpaid invoice feels like a personal slight, especially when you've done good work and built what felt like a decent relationship. Most of the time it isn't personal. People avoid awkward money conversations the same way you might avoid chasing them, it's discomfort, not malice, in the majority of cases. That doesn't make it okay, but it changes how you should approach fixing it.
Step 1: Send one plain, unemotional reminder
Before assuming the worst, send a short, neutral message. Not apologetic, not accusatory, just a fact.
"Hi [name], just flagging that invoice #[number] for £[amount] was due on [date] and I haven't seen payment come through yet. Let me know if there's an issue on your end."
That last line matters. It gives them a face-saving way to explain a genuine problem, a card issue, they forgot, they're waiting on their own client, without you having assumed bad faith. Most unpaid invoices get resolved at this stage.
Step 2: If there's no reply in 3-5 days, follow up once more, slightly firmer
"Hi [name], following up on invoice #[number], now [X] days overdue. Could you let me know when I can expect payment?"
Still polite, but the ambiguity is gone. You're not asking if there's an issue anymore, you're asking for a date.
Step 3: Call, don't just message, if you have a number
This is the step most people skip because it feels more confrontational, but it's usually the most effective one. A message is easy to leave on read. A phone call is much harder to ignore, and most people would rather explain themselves on a two minute call than keep dodging texts. If they don't pick up, a voicemail asking them to call you back about the invoice works nearly as well as getting through.
Step 4: Send a final notice with a clear deadline
If you've had no response after a call attempt and a couple of messages, it's time to be direct in writing.
"Hi [name], I haven't been able to reach you about invoice #[number], now [X] days overdue. If I don't hear back by [specific date], I'll need to consider next steps, which may include late payment charges or referring this to a collections service."
You don't have to actually intend to do either of those yet, the point of this message is that it signals seriousness. A deadline with real consequences attached gets more responses than an open-ended request.
Step 5: Know your actual legal options
As a UK sole trader, you're entitled to charge statutory interest on overdue B2B invoices under the Late Payment of Commercial Debts Act, currently the Bank of England base rate plus 8%, plus a fixed compensation fee depending on the invoice size. This applies to business clients, not typically individual consumers, so check which situation you're in before threatening it.
For genuinely unresponsive clients on larger amounts, the Money Claim Online service (via gov.uk) lets you file a small claim without a solicitor for a modest fee, and for many clients simply receiving that formal notice is enough to prompt payment before it goes further.
When to just let it go
Honestly, sometimes the maths doesn't work in your favour. Chasing a £40 invoice through formal channels can cost more in time and stress than the amount itself. It's worth being clear-eyed about which invoices are worth escalating and which aren't, without letting that become a habit clients learn to exploit.
How Cleared helps with this
Cleared tracks which invoices are outstanding and how overdue they are without you needing to keep a mental list. When you're ready to chase, you just say "chase [client name]" and a professional reminder goes out on your behalf, so you're not stuck drafting the awkward message yourself every time.
Frequently asked questions
How long should I wait before chasing an unpaid invoice?
Send a polite reminder as soon as it's overdue, even by a day or two. Waiting too long makes it easier for the client to have genuinely forgotten, and harder for you to raise it without feeling like it's a bigger deal than it should be.
Can I charge interest on a late invoice?
Yes, under the Late Payment of Commercial Debts Act, for business clients. The current rate is the Bank of England base rate plus 8%, plus a fixed compensation amount. This doesn't typically apply to individual consumer clients.
What if the client just stops responding entirely?
Escalate through the steps: message, firmer message, phone call, final written notice with a deadline. If that fails on a meaningful amount, Money Claim Online is a low-cost way to formally pursue it without a solicitor.
Is it worth chasing small unpaid invoices?
Often not through formal channels, the time and stress can outweigh the amount. Still worth a reminder message, just be realistic about when to let a small one go versus when to escalate.