How to Write an Invoice That Actually Gets Paid (UK Guide)

Half of the UK's smallest businesses get paid late, and it usually starts with an invoice that left something out.

Three mistakes people make

Writing "30 days" instead of a date

Thirty days from when? A due date the client can put in their diary gets paid faster than a rule they have to work out themselves.

Getting the VAT line wrong

Charging VAT without being registered is an offence, not a rounding error, and forgetting a VAT line when you are registered is just as much of a problem.

Chasing by memory, not in writing

A polite reminder the day before the due date gets more invoices paid than a phone call three weeks late. Most unpaid invoices are not disputes, they are invoices nobody actioned.

The fix: the nine fields, filled in for you

The Jobbit invoice generator asks who it is for, the amount, what it was for, whether VAT applies and the payment terms, then lays out a numbered PDF with an itemised list, a bank details block and an editable DOCX copy. Your details are remembered, so the next invoice is a one-line job. The nine fields UK law expects are covered in full in the original guide.

How the free options compare

What you need	Templates and apps	Jobbit
Correct sums and numbering	A Word template leaves both to you	Subtotal, VAT and total calculated
More than a few a month	Invoice Simple allows three free invoices	As many as the daily credits cover
The reminder emails	Written separately, or not at all	Drafted in the same chat

A mobile hairdresser's regulars

A mobile hairdresser invoices the same six regular clients every month. Each invoice used to be a fresh Word document; now it is one sentence to Jobbit with the client's name and the amount, and the layout and her bank details are already there from last time.

When to pay instead

If you want card payments taken automatically and reconciled against a bank feed, or a full set of accounts for Making Tax Digital, that is what Xero, FreeAgent or a proper invoicing app are for. For getting a correct invoice out the door today, a free generator does the job.

Frequently asked questions

What does a UK invoice legally need to include?

The word Invoice, a unique number, your business details, the client's details, a clear description of the work, the date, the amount and the payment terms. VAT-registered businesses also add their VAT number and rate.

What happens if a client pays my invoice late?

Business customers who pay late owe statutory interest of 8% above the Bank of England base rate, plus a fixed fee of 40, 70 or 100 pounds depending on the size of the debt, whether or not your invoice mentions it.

Do I need to charge VAT?

Only if you are VAT registered, which becomes compulsory once your taxable turnover passes 90,000 pounds in a rolling 12 months. Below that, leave VAT off the invoice entirely.