How to create a proper UK invoice as a sole trader

What to include on your invoice

Keep the invoice clear enough that the customer can understand what it covers. The official requirements are set out in the GOV.UK invoice checklist.

• Your trading name, contact details and business address.
• If you use a trading name, your own legal name and an address where legal documents can be delivered.
• The customer's name and address.
• A unique invoice number, the invoice date and the date the goods or services were supplied.
• A clear description of the work or goods and the amount charged for each.
• The total before VAT, VAT where applicable, and the final total due.
• Useful payment information, including the due date, bank details and payment reference.

Use descriptions customers understand

Good descriptions reduce back-and-forth. "Replace kitchen tap, including fittings" is stronger than "plumbing work". "Boiler service and safety check" is stronger than "labour".

Do you need VAT on the invoice?

If your business is VAT registered, a VAT invoice has extra required information beyond your VAT number and the total VAT. Follow the official VAT-invoice checklist and keep the records described in GOV.UK VAT record guidance. If you are not VAT registered, do not charge VAT. SayInvoice can put your saved VAT preference into an editable draft, but you remain responsible for checking the rate, figures and wording.

Invoice numbers and dates

Use a numbering system you can keep using. It does not need to be complicated, but every invoice should have its own number so you, your customer, and your accountant can find it later. Many sole traders use a short prefix, then a running number such as SI-001, SI-002, and SI-003.

The invoice date is the date you issue the invoice. The due date is when you expect payment. Putting both on the PDF makes the payment expectation much clearer than sending a message that simply says "please pay when you can".

Common invoice gaps to avoid

Small gaps can leave the customer unsure what they are being charged for or how to pay.

• Using vague descriptions such as "work completed" instead of clear job lines.
• Forgetting to include bank details or a payment reference.
• Changing invoice numbers manually and accidentally creating duplicates.
• Adding VAT when you are not VAT registered.
• Sending the invoice days later, once the job details are harder to remember.

Put payment details in one place

Put the total due, payment terms, bank details and payment reference somewhere the customer can see clearly. For repeat customers, consistent wording also makes each document easier to recognise.

Example voice note for a sole trader invoice

That kind of note gives the app enough structure to create a useful draft. You can still edit the wording, change the price, add VAT if needed, and check the customer details before choosing how to share it.

Frequently asked questions

Can a sole trader send invoices without a company number?

Yes. A sole trader does not have a limited company number. Use your trading name or your own name, your business contact details, and clear payment information.

Should I include my home address?

Your invoice should include business contact details. If you are unsure what address to use, check with your accountant so your paperwork matches how your business is set up.

Can I send invoices by WhatsApp?

You can open WhatsApp or another share option with the PDF, then choose the recipient and complete the send yourself. Marking a document as sent records your action; it does not prove the customer received, opened or read it.

How SayInvoice reduces repeated typing

Save your business details, bank details, payment terms, invoice prefix, and VAT preference once. After that, speak the job into your phone, check the draft, and choose WhatsApp, email or another share option for the clean PDF. You complete the final send in the app you choose.