UK Invoice Requirements: Plain Invoices and VAT Invoices

If you are not VAT registered

You still have to issue a proper invoice, and GOV.UK sets out what it must include: a unique identifying number, your business name, address and contact information, the name and address of the customer, a clear description of what you are charging for, the date of supply, the invoice date, the amount being charged, and the total owed.

What you must not do is show a VAT line or a VAT registration number. Charging VAT when you are not registered for it is a serious problem, and adding a plausible-looking VAT line to make an invoice look more professional is the most common way small businesses stumble into it.

Sole traders should show their own name alongside any trading name. A limited company should use its full registered name as it appears on the certificate of incorporation.

When you need a full VAT invoice

Once registered, the supply value decides the format. Where the consideration exceeds £250 including VAT you need a full VAT invoice. At or below £250 a simplified invoice is acceptable, which is why shop receipts look nothing like a contractor invoice.

HMRC lists the details a full VAT invoice must show in its internal manual, which is the most precise statement of the requirement available.

• A sequential number that uniquely identifies the document
• The time of supply — the tax point — and the date of issue where they differ
• Your name, address and VAT registration number
• The name and address of the customer
• A description sufficient to identify the goods or services supplied
• For each description: the quantity, the VAT rate, and the amount payable excluding VAT
• The unit price
• The gross total payable excluding VAT
• The rate of any cash discount offered
• The total VAT chargeable, expressed in sterling

Simplified and modified invoices

A simplified VAT invoice covers supplies of £250 or less including VAT. It needs your name, address and VAT number, the time of supply, a description identifying what was supplied, and for each VAT rate the total payable including VAT and the rate charged. Exempt supplies must not appear on a simplified invoice at all.

A modified VAT invoice is the third option: for supplies above £250, and only where the customer agrees, you can show VAT-inclusive rather than VAT-exclusive values for each item. It exists for retail-style businesses and is worth knowing about mainly so you recognise one when a supplier sends you it.

The registration threshold

You must register for VAT once your taxable turnover in any rolling twelve months exceeds £90,000, a threshold that rose from £85,000 on 1 April 2024. Registration is required within 30 days of the end of the month you crossed it, and your effective date is the first day of the second month after that. GOV.UK covers the thresholds including the £88,000 figure at which you may deregister.

The rolling twelve-month test catches people out. It is not your financial year — a strong autumn can push you over on a measurement window that ends in November, and the obligation starts then rather than at your year end.

What you can charge when payment is late

Between businesses, statutory interest is 8% plus the Bank of England base rate. The base rate is fixed twice a year for this purpose: the rate on 31 December applies for the first half of the following year, and the rate on 30 June applies for the second half.

You can also claim a fixed sum towards the cost of recovering the debt, on top of the interest, and the amount steps up with the size of the debt. Check the current bands on the GOV.UK page rather than relying on a figure quoted elsewhere.

Two limits are worth knowing. You cannot claim statutory interest if your contract sets a different rate — though you cannot use a lower rate when contracting with a public authority — and interest can only be collected for up to six years from the day after the contracted payment terms ended.

Keeping the records

VAT records generally need to be kept for six years, and VAT Notice 700/21 sets out what counts as a record and the form it can take. Copies of the invoices you issued are part of that, not an optional extra.

Digital copies are fine provided they are complete and readable. If you are within Making Tax Digital, the requirement extends to keeping the underlying records digitally and preserving the link between them and your return, so a PDF filed in a folder is the floor rather than the whole answer.

UK invoicing: common questions

Sources

1. Invoices — what they must include — GOV.UK
2. VATREC5010 — details which must be shown on a full VAT invoice — HM Revenue & Customs
3. Late commercial payments: charging interest and debt recovery — GOV.UK
4. Record keeping (VAT Notice 700/21) — HM Revenue & Customs

More on by country

• US Invoice Requirements: What Actually Applies

  There is no federal invoice format in the US. What actually governs is your contract, state sales tax, and the W-9 and 1099-NEC paperwork.

• Canada GST/HST Invoice Requirements

  The CRA information requirements at each dollar threshold, why the rate depends on the buyer's province, and the $30,000 small supplier line.

• Australian Tax Invoice Requirements

  The seven details the ATO requires on a tax invoice, the $82.50 and $1,000 thresholds, and how GST rounding works.

• GST Invoice Format in India: Every Mandatory Field

  The 16 fields Rule 46 requires on a GST invoice, how CGST/SGST/IGST is decided, HSN digit rules by turnover, and what breaks your buyer's input tax credit.

• UAE Tax Invoice Format: What the FTA Requires

  What Article 59 requires on a UAE tax invoice, when the simplified format is allowed, and how the AED 10,000 threshold works.

• EU VAT Invoices: Reverse Charge and Cross-Border Rules

  Cross-border EU invoicing: when to use reverse charge, the exact wording the VAT Directive requires, validating a customer VAT number, and what changes for non-EU sellers.

• Invoice Requirements in the Philippines After the EOPT Act

  How the Ease of Paying Taxes Act changed Philippine invoicing: the sales invoice is now primary, the official receipt is supplementary, and what that means for VAT.

• Nigeria VAT Invoice Format and FIRS E-Invoicing

  Nigerian VAT invoice requirements, the FIRS e-invoicing mandate and its IRN and QR validation, plus how withholding tax changes what you actually receive.