The Best Invoice Format for UK Freelancers

UK invoicing differs from US invoicing in one important respect: there are actual published requirements. GOV.UK sets out what an invoice must contain, HMRC sets out considerably more for VAT invoices, and the Companies Act adds rules for limited companies.

This guide covers what is genuinely required for each business structure, what is merely good practice, and the statutory late-payment rights that a surprising number of freelancers never invoke.

What every UK invoice must include#

According to GOV.UK guidance on invoicing, an invoice must:

• be clearly marked "invoice"
• include a unique identification number
• include your company name, address and contact information
• include the company name and address of the customer being invoiced
• carry a clear description of what you are charging for
• state the date the goods or service were provided (the supply date)
• state the date of the invoice
• state the amount(s) being charged
• state VAT amount if applicable
• state the total amount owed

That first point is easy to overlook. The word "invoice" has to appear. A document headed "Statement" or "Summary of work" is not an invoice, and in a payment dispute the distinction matters.

Requirements by business structure#

Sole traders#

If you trade as a sole trader you must include:

• your own name, and any business name you are using
• an address where legal documents can be delivered, if you are using a business name

So "Ada Lovelace, trading as Lovelace Design" with a deliverable address satisfies it. A trading name and a Gmail address does not.

You do not need a company registration number, because you do not have one. You do not need to be VAT registered unless you are over the threshold.

Limited companies#

If you have incorporated, you must include:

• the full company name as it appears on the certificate of incorporation — including "Limited" or "Ltd", spelled the way Companies House has it
• if you choose to name any director on the invoice, you must name all of them

That second rule catches people out. It is all or none: listing one director as a contact obliges you to list the whole board.

In addition, standard business practice — and the Companies Act requirements for business letters and websites, which most companies apply to invoices too — means including your registered office address and company registration number. Both are also the kind of thing a client's finance team will ask for if it is missing.

VAT-registered businesses#

If you are VAT registered, the invoice becomes a VAT invoice and HMRC requires considerably more. A full VAT invoice must show:

The tax point is worth understanding rather than guessing at. It is the date the supply is treated as taking place for VAT purposes, and it determines which VAT return the transaction falls into. For most freelance services it is the invoice date, provided the invoice is issued within 14 days of the supply — but if payment is received first, or the invoice is issued late, the rules shift. If you are near a quarter-end, this is worth getting right.

Simplified and modified VAT invoices exist for retail and for totals over £250 respectively, but neither is typically relevant to freelance service work.

When do you have to register for VAT?#

Registration is compulsory when your VAT-taxable turnover exceeds the threshold over any rolling 12-month period — not your accounting year — or when you expect to exceed it in the next 30 days alone.

The threshold is £90,000 as at this guide's review date. Confirm the current figure on GOV.UK before making a decision, since thresholds change with fiscal announcements.

Two practical notes. "Rolling 12 months" means you should be checking monthly, not annually; plenty of freelancers discover they crossed the threshold four months ago. And voluntary registration below the threshold is sometimes worth it — if your clients are themselves VAT registered they reclaim the VAT you charge, and you reclaim VAT on your own costs.

Building the invoice, field by field#

1. Your details#

Business or trading name, your own name if a sole trader, deliverable address, email, phone. VAT number if registered. Company number and registered office if incorporated.

2. Client details#

The client's registered company name and address. As with the US, this should be the legal entity, not the brand. Include a purchase order number if one was issued — in any organisation with a procurement function, a missing PO number will silently stall the payment.

3. Invoice number#

Unique, sequential, never reused. 2026-014 or INV-0142 both work. For VAT invoices, HMRC expects the sequence to be unbroken; if you void one, keep a record of why rather than reusing the number.

4. Dates#

Two dates, both required: the invoice date and the supply date (when the work was done or delivered). They are frequently the same and are not always. Add a due date as well — not legally required, but the single most useful thing on the document.

5. Description#

Enough detail that someone in finance who has never met you can match it to an approved piece of work. Reference the contract or statement of work. For hourly work, say what the hours covered.

6. Amounts#

Quantity, unit price excluding VAT, line total. Then net total, VAT (per rate, if you have items at different rates), and gross total. VAT must be shown in sterling even if the invoice is otherwise in another currency.

7. Payment details#

• Account name, sort code and account number for a UK transfer
• IBAN and BIC for international payments
• Ask for the invoice number as the payment reference

8. Payment terms#

State them in words. If your contract sets terms, repeat them here. If it does not, the default position under the Late Payment Act applies — see below.

Statutory late payment rights, which you should actually use#

This is the part most freelancers do not know exists.

The Late Payment of Commercial Debts (Interest) Act 1998 gives you an automatic statutory right to interest and compensation on overdue commercial debts. It applies between businesses; it does not apply to consumers.

When payment becomes late. If the contract sets a payment period, that governs — but for business-to-business contracts, a period longer than 60 days is only permitted if it is expressly agreed and is not grossly unfair to the supplier. For public authorities the limit is 30 days. If no terms were agreed, the default is 30 days after the later of: the customer receiving the invoice, or delivery of the goods or service.

What you can charge. Statutory interest at 8% above the Bank of England base rate, running from the day after payment was due. Plus a fixed sum for debt-recovery costs:

If your reasonable recovery costs exceed the fixed sum — for example, you instructed a debt-recovery agent — you can claim the difference.

You do not need this written into your contract. The right is statutory and applies unless the contract provides a "substantial remedy" for late payment instead.

How to use it. In most cases you never invoice the interest; you mention it. A line in a chase email — "the invoice is now 21 days overdue and is accruing statutory interest under the Late Payment of Commercial Debts (Interest) Act 1998, currently £X, plus £70 in recovery costs" — is a specific, correct, entirely reasonable statement that tends to move an invoice up a payment queue considerably faster than "just checking in on this."

Record keeping#

Sole traders and partnerships: keep records for at least five years after the 31 January submission deadline for the relevant tax year. So for the 2025–26 tax year, filed by 31 January 2027, records must be kept until at least 31 January 2032.

Limited companies: keep records for six years from the end of the accounting period they relate to, and longer where a transaction spans more than one period or a return was filed late.

VAT records: six years, and they must be kept in a form HMRC can inspect. Under Making Tax Digital for VAT, VAT-registered businesses must keep digital records and file through compatible software.

Keep a copy of every invoice you issue, in a format you can still open years later. PDF is the sensible choice.

A UK freelance invoice checklist#

• The word "invoice" appears on the document
• Unique, sequential invoice number
• Your name / trading name and deliverable address
• Full company name, registration number and registered office (limited companies)
• All directors named, or none (limited companies)
• Your VAT number (if registered)
• Client's registered name and address
• Purchase order number, if one was issued
• Invoice date
• Supply date / tax point
• Payment due date
• Clear description of the work
• Quantity, unit price and line total, excluding VAT
• VAT rate and amount per item, in sterling
• Net total, VAT total, gross total
• Bank details, including IBAN and BIC for overseas clients
• Payment terms in words
• Sent as a PDF, to the right address

Common mistakes#

Omitting the word "invoice". Legally required, trivially fixed.

Using a trading name without an address. A sole trader using a business name must give an address where legal documents can be delivered.

Charging VAT before registration. You cannot charge VAT until you are registered. If you have applied and are waiting for your number, the correct approach is to raise your prices by the VAT amount, issue invoices without a VAT line, then reissue proper VAT invoices once your number arrives.

Missing the tax point. Particularly around quarter-ends, where it decides which return the sale falls into.

Not stating a due date. Without one, the statutory default applies — which may be later than you assumed, and is certainly later than you wanted.

Ignoring statutory interest. It costs nothing to mention, and it is your legal right.

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Our free invoice generator supports GBP, VAT rates and automatic due dates from your chosen terms, and produces a PDF entirely in your browser.

Also worth reading: Net 15 vs Net 30 vs Net 60 for choosing terms, what should be included in a US invoice if you bill American clients too, and how to make an invoice without software.

This guide is general information about UK requirements as at the review date. It is not accounting, tax or legal advice. Check GOV.UK for current thresholds and speak to an accountant about your own position. See our disclaimer.