Daily Junction.mobi portalBusiness · July 11, 2025 · Marcus Vale · 5 min
An invoice is a formal request for payment that records what you supplied and what you are owed. This UK guide covers exactly what to put on one, the VAT rules, and how to get paid faster.
Sending an invoice is how most businesses actually get paid — yet a surprising number are scrappy, unclear or missing details that the law requires. A well-built invoice does two jobs at once: it satisfies the rules, and it makes it easy and obvious for the customer to pay you promptly. This guide walks through what to put on a UK invoice, when VAT applies, and the small touches that get cash in faster. This is general business information, not tax or legal advice.
An invoice is a formal, dated document that requests payment, recording what you supplied to a customer and the total they owe. It is more than a polite note — it is a commercial record that both sides rely on for accounts and tax.
It helps to be clear about what an invoice is not. A quote is an estimate of price before work begins. A receipt confirms payment after it has been made. An invoice sits in between: the request for money once goods or services have been delivered. Keeping these distinct avoids confusion and looks professional. When you record the invoice in your books also depends on whether you use cash or accrual accounting, which we cover separately.
Getting invoicing right is part of the wider discipline of managing money in a business. Our guide to cash flow in a small business explains why the timing of payments matters as much as the amounts.
There is a core set of details that should appear on any invoice. Leaving them out can delay payment or cause problems with your records.
For a limited company, there are extra requirements, such as showing the full registered company name and, often, the registered number. It is worth confirming the current detail on GOV.UK, since the rules differ slightly by business type.
VAT is where invoices get more involved, and the rule depends entirely on your status.
If your business is not VAT-registered, you do not charge VAT and your invoice simply shows the amounts due. You must register once your taxable turnover passes the VAT threshold, and you can choose to register voluntarily below it.
If your business is VAT-registered, you must issue a proper VAT invoice, which includes everything above plus:
Because thresholds and the finer points change, always check the current position on GOV.UK rather than relying on an old figure. Whatever your status, keep copies of every invoice — they are a key part of your records and you may need them at tax time. The totals on your invoices also feed straight into your accounts, including your profit and loss statement, so accuracy here pays off later.
You do not need fancy design — clarity beats decoration. A clean structure might look like this:
| Section | What goes here |
|---|---|
| Header | The word "Invoice", your logo or business name, invoice number and date |
| From / To | Your details and the customer's details |
| Body | Itemised description, quantity, unit price and line totals |
| Totals | Subtotal, VAT if applicable, and the grand total due |
| Footer | Payment terms, due date and how to pay |
Spreadsheet templates, free online tools and accounting software all produce this format. The important thing is consistency: a tidy, repeatable layout makes your business look organised and your invoices easy to process at the other end.
The mechanics matter, but so does the psychology of prompt payment. A few habits make a real difference:
Under UK law, if you do not agree a payment period, payment is generally due within 30 days. For overdue commercial invoices, you may also be entitled to claim statutory interest and a fixed recovery cost — a useful backstop, though a good relationship and clear terms usually prevent things getting that far.
Even with everything in order, some invoices run late. A calm, escalating approach works best:
GOV.UK sets out your rights on late commercial payments, including how interest is calculated. Keeping records of every invoice and reminder puts you in a strong position if a dispute ever arises.
An invoice is a formal request for payment that records what you supplied and what you are owed — and getting it right is the difference between being paid promptly and chasing for weeks. Include the core details and a unique number, follow the VAT rules if you are registered, set clear terms with a due date, and make paying easy. Do that consistently, and most invoices look after themselves.
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