How to Invoice as a Sole Trader in the UK — What You Actually Need

Invoicing isn't complicated, but there's a difference between an invoice that's technically correct and one that actually gets you paid quickly. Most sole traders learn this the hard way — an awkward customer finds a reason to query the invoice, payment gets pushed back three weeks, and you're the one chasing.

Here's what needs to be on every invoice you send, what HMRC requires, and what separates the invoices that get paid promptly from the ones that sit in someone's inbox for a month.

What the law actually requires

As a sole trader, HMRC requires that your invoices include specific information. Every invoice must include:

Your full name — your legal name, not just a trading name. If you trade as "JT Electrical" you still need "John Turner trading as JT Electrical." Your business address — a physical address, not just a phone number or email. An invoice number — must be unique and sequential. The date of supply — when the work was done, not just when you raised the invoice. The invoice date — when the invoice was issued. A description of the goods or services — specific enough to be meaningful. The amount charged — clear, itemised where appropriate. The customer's name and address — who you're billing.

Invoice numbering — don't skip this

Sequential invoice numbering is one of those things people ignore until they're sitting in front of an accountant or HMRC inspector who wants to know what happened between invoice 47 and invoice 63.

Start at 001 and go up. Some people use a year prefix — DR2025-001, DR2025-002 — which makes it easy to see at a glance when something was raised. Whatever system you pick, stick to it and never reuse a number, even if you cancel an invoice.

If you delete invoice 14 because you made an error, the correct approach is to issue a credit note referencing invoice 14, then raise a new invoice 15 with the corrected information.

Describing the work properly

This is where most sole traders are too vague. "Electrical works" or "plumbing repairs" isn't a description — it's a category. Compare:

Bad: "Electrical works at property — £650" Better: "Supply and fit 2x double sockets in kitchen, replace consumer unit, test and certify — 2 days labour" The second version is harder to dispute. It's clear what was done, what was included, and how long it took. For jobs with materials, list them separately. Labour on one line, materials on another.

Payment terms — be specific

If your invoice just says "payment due on receipt," you're leaving the door open for interpretation. State a specific due date or a number of days. "Payment due within 14 days of invoice date" is clear and gives you a solid basis for chasing if it's not paid.

For regular customers, 30 days is standard. For one-off jobs, especially for customers you don't know well, 14 days is reasonable.

How to get paid faster Include your bank details on the invoice — account name, sort code, account number. Sounds obvious, but plenty of people forget and then have to field a call asking for the details before payment goes through.

Send the invoice the same day the job finishes. Every day you wait to send it is another day added to when you'll actually see the money.

VAT invoices — additional requirements

If you're VAT registered, your invoices need:

Your VAT registration number The VAT rate applied to each item The net amount before VAT The VAT amount The gross total including VAT If you're doing work under the VAT reverse charge, you don't add VAT. Instead, note on the invoice: "VAT reverse charge applies — customer to account for VAT at 20%."

Keeping records

HMRC requires sole traders to keep records for at least five years after the 31 January Self Assessment deadline following the relevant tax year — around six years in practice.

Digital records are fine. Keep your invoices organised by year and number, and back them up somewhere that isn't just your phone.

Dayrates keeps all your invoices in one place, numbered automatically, with a full audit trail — so when your accountant or HMRC asks for records, you're not digging through a WhatsApp thread or a drawer full of paper.

The one mistake that causes the most payment delays Vague invoice descriptions. Every time. A customer who wants to delay payment will find a reason to query a vague invoice. "Can you clarify what works this covers?" buys them another two weeks.

Be specific upfront. Itemise the labour, list the materials, reference the quote if there was one. Give them nothing to query and most decent customers will just pay.