If your business is VAT-registered, your invoices are not just payment requests — they are legal documents. HMRC sets out exactly what a VAT invoice must contain, how soon it must be issued, and what happens when it is wrong. A missing VAT number or a wrong rate can mean your customer cannot reclaim the VAT you charged, and it can leave you exposed to penalties. This guide covers everything a UK VAT invoice must include in the 2026/27 tax year, the three invoice types (full, simplified and modified), the £250 simplified-invoice threshold, the 30-day issuing deadline, electronic invoicing rules and worked £ examples of correct invoices.
A quick refresher for 2026/27: the UK VAT rates are 20% (standard), 5% (reduced) and 0% (zero). The VAT registration threshold is £90,000 of taxable turnover in any rolling 12-month period. Only VAT-registered businesses may charge VAT on their invoices — charging VAT without being registered is not allowed, and HMRC can require you to hand over any VAT you wrongly charged.
Why VAT Invoices Matter
A VAT invoice does three jobs at once. First, it is your customer's evidence for reclaiming input VAT — without a valid VAT invoice, they cannot recover the VAT you charged them, which can strain the relationship fast. Second, it is your own evidence: it proves the output VAT you declared on your VAT return was calculated correctly. Third, it is HMRC's audit trail: during a VAT inspection, your invoices are the first thing officers check, line by line.
That is why "getting the invoice right" is not admin fiddliness but a core VAT compliance task. The requirements come from HMRC's VAT invoicing rules (VAT Notice 700/21), and they apply to every VAT-registered business, from sole traders to limited companies.
The 11 Things Every VAT Invoice Must Include
A full VAT invoice — the standard type used for supplies over £250 including VAT — must show all of the following:
- A sequential invoice number. Numbers must run in sequence with no gaps or duplicates, so every invoice is uniquely identifiable. Restarting numbering each financial year is fine as long as the sequence is unbroken within each series.
- Your business name and address. The legal name of the VAT-registered business making the supply.
- Your VAT registration number. Your 9-digit VAT number, usually shown as "VAT No. GB 123 4567 89". This is the single most-checked field on an invoice.
- The date of issue. The date the invoice itself is raised.
- The time of supply (tax point). The date the supply took place, which determines the VAT period it falls into. If this is the same as the invoice date, you can simply note that.
- Your customer's name and address. Required on full invoices (simplified invoices, covered below, can omit this).
- A description of the goods or services. Enough detail to identify what was supplied — "consultancy" is weak; "5 days management consultancy, 12–16 May 2026" is right.
- The quantity of goods or extent of services, with unit prices. How many were supplied and at what price each, excluding VAT.
- The VAT rate charged. The rate applying to each line — 20%, 5% or 0% — shown per line item when rates differ.
- The amount payable excluding VAT, per line and in total. The net value of each line and the invoice subtotal before VAT.
- The VAT amount and the total payable. The total VAT charged and the grand total including VAT.
Miss any of these on a full invoice and it is technically not a valid VAT invoice — your customer may be refused the input VAT reclaim, and HMRC can disallow it on inspection.
Worked Example: A Correct VAT Invoice
Here is how those requirements look in practice for a straightforward 20%-rated supply:
Invoice No. 1042 — issued 12 May 2026
- Supplier: Brightline Marketing Ltd, 14 King Street, Leeds LS1 2HL — VAT No. GB 842 1190 55
- Customer: Harrogate Fitness Ltd, 3 Montpellier Parade, Harrogate HG1 2TJ
- Time of supply: 12 May 2026
| Description | Qty | Unit price (ex VAT) | VAT rate | Net | VAT |
|---|---|---|---|---|---|
| Social media management, May 2026 | 1 | £800.00 | 20% | £800.00 | £160.00 |
| Design assets package | 1 | £450.00 | 20% | £450.00 | £90.00 |
| Totals | £1,250.00 | £250.00 |
Total payable including VAT: £1,500.00
Check the arithmetic: £800 × 0.20 = £160; £450 × 0.20 = £90; net total £1,250; VAT total £250; gross £1,500. Every required element is present: sequential number, both parties' details, VAT number, dates, descriptions, per-line rates, net and VAT figures, and the grand total. This invoice lets Harrogate Fitness reclaim £250 of input VAT with no questions asked.
Full vs Simplified vs Modified Invoices
Not every supply needs all 11 elements. HMRC provides two lighter invoice types for specific situations:
| Invoice type | When to use | What it must show |
|---|---|---|
| Full VAT invoice | Supplies over £250 including VAT | All 11 elements listed above |
| Simplified VAT invoice | Supplies of £250 or less including VAT | Your name, address and VAT number; time of supply; description of goods/services; total including VAT; and either the VAT amount or the VAT rate applied |
| Modified VAT invoice | Retail supplies over £250 where a full invoice is impractical (e.g. coin-operated machines) | Your name, address and VAT number; time of supply; description; total including VAT; and, for each VAT rate charged, the gross amount and the VAT included at that rate |
The £250 threshold is the key number: at or below £250 including VAT, a simplified invoice is acceptable; above it, you need the full version (unless the modified-invoice rules apply). A simplified invoice still has to show the VAT number and enough detail to identify the supply — "goods £200 + VAT" on a till receipt with no business name or VAT number is not a simplified VAT invoice, and the customer cannot reclaim from it.
A common trap: splitting a £400 supply into two £200 invoices to stay under the threshold. HMRC treats deliberately split supplies as a single supply, so the full-invoice requirement stands.
Electronic Invoices
Paper is not required. You can issue VAT invoices electronically — by email, through accounting software, or via an e-invoicing platform — as long as two conditions hold: the customer agrees to receive invoices electronically, and you can guarantee the authenticity of origin and integrity of content (in practice, sending a PDF from your normal business email or a reputable invoicing system satisfies this).
Electronic invoices carry exactly the same content requirements as paper ones: a PDF missing the VAT number is just as invalid as a paper invoice missing it. Keep electronic copies for the same retention period — you must keep VAT records for at least 6 years.
The 30-Day Deadline
You must issue a VAT invoice within 30 days of the time of supply — the date the goods were delivered or the service performed. If the 12th of the month is the tax point, the invoice must go out by the 11th of the following month at the latest.
Late invoicing causes two problems. First, your customer cannot reclaim the VAT until they hold the invoice, so delays directly hit their cash flow — and their patience. Second, consistently late or missing invoices are a red flag in a VAT inspection. If you invoice in arrears (for example, monthly billing for ongoing work), diarise the deadline; accounting software that auto-generates invoices on a schedule makes this automatic.
Note the interaction with Making Tax Digital: since April 2022, all VAT-registered businesses must keep digital records and file VAT returns through MTD-compatible software. Your invoicing system should feed those digital records — a shoebox of paper invoices does not meet the requirement.
Mixed-Rate Invoices: A Worked Example
Many invoices carry more than one VAT rate — a café wholesaler billing both standard-rated equipment and reduced-rate items, for instance. The rule is simple: show each rate separately, per line, with separate subtotals. Here is a mixed-rate example:
Invoice No. 2087 — issued 3 June 2026
- Supplier: Northern Catering Supplies Ltd — VAT No. GB 310 8842 17
- Customer: Bingley Café Ltd
| Description | Net | VAT rate | VAT |
|---|---|---|---|
| Commercial coffee machine | £1,200.00 | 20% | £240.00 |
| Energy-saving lighting installation | £600.00 | 5% | £30.00 |
| Totals | £1,800.00 | £270.00 |
Total payable including VAT: £2,070.00
Arithmetic check: £1,200 × 0.20 = £240.00; £600 × 0.05 = £30.00; net £1,800; VAT £270; gross £2,070. The per-rate breakdown lets the customer reclaim exactly £270 and lets you post the correct output VAT per rate on your VAT return (Boxes 1 and 6 of the return need rate-level accuracy — see our guide to VAT return boxes).
What Happens If You Get It Wrong
Invoice errors have concrete consequences:
- Your customer loses the reclaim. If your invoice is missing the VAT number or the VAT amount, your customer cannot reclaim the input VAT — they effectively pay 20% more than they should, and they will come back to you.
- HMRC can disallow your figures. During an inspection, invalid invoices undermine your declared output VAT and your customers' input VAT claims. Systematic errors can trigger penalties.
- Wrong-rate invoices compound. Charging 20% on a 5%-rated supply overcharges the customer; charging 5% on a 20%-rated supply underpays HMRC. Both are correctable with a credit note and a corrected invoice, but only if you catch them.
- Missing invoices suggest missing supplies. Gaps in your sequential numbering invite HMRC to ask what the missing invoices were for.
The fix for a genuine error is straightforward: issue a credit note cancelling the wrong invoice and raise a corrected one. Do this as soon as the error is spotted — correcting voluntarily before an inspection looks far better than being found out.
FAQs
What must a UK VAT invoice include?
A full VAT invoice must show: a sequential invoice number; your name, address and VAT registration number; the issue date; the time of supply; the customer's name and address; a description of the goods or services; quantities and unit prices; the VAT rate per line; net amounts per line and in total; the total VAT; and the total including VAT.
When can I use a simplified VAT invoice?
For supplies of £250 or less including VAT. A simplified invoice must still show your name, address and VAT number, the time of supply, a description of the supply, the total including VAT, and the VAT amount or rate. Above £250 you need a full VAT invoice.
How quickly must I issue a VAT invoice?
Within 30 days of the time of supply (the date the goods were delivered or the service was performed). Late invoices delay your customer's input VAT reclaim and raise questions in a VAT inspection.
Can I send VAT invoices by email?
Yes, if the customer agrees to electronic invoicing and you can ensure the authenticity and integrity of the invoice — in practice, a PDF from your business email or accounting software qualifies. Electronic invoices must contain exactly the same information as paper ones, and you must keep copies for at least 6 years.
What happens if my invoice is missing the VAT number?
It is not a valid VAT invoice, and your customer cannot reclaim the input VAT shown on it. Issue a corrected invoice with the VAT number included as soon as you spot the error.
Do I need separate invoices for different VAT rates?
No — one invoice can carry multiple rates, but each line must show its rate, and you should subtotal by rate. For example, £1,200 at 20% (£240 VAT) plus £600 at 5% (£30 VAT) gives £1,800 net, £270 VAT and £2,070 gross.
Internal links: /how-to-add-vat-to-a-price-uk/, /vat-return-boxes/, /when-to-register-for-vat-uk/, /can-sole-trader-claim-vat-back/ Author: VAT Calculator Team
Educational information and estimates. These tools do not submit VAT returns or determine the treatment of a specific transaction.