How to Write a Professional Invoice UK

How to Write a Professional Invoice as a Sole Trader Most disputes about payment don't start with a difficult customer. They start with a vague invoice. Wrong date, missing VAT number, no payment terms — all of it gives a slow payer an excuse to delay. Here's what every invoice needs to include if you're a sole trader in the UK, and how to make sure you're sending something that actually gets paid.

What Must Every Invoice Include?

HMRC has specific requirements for invoices. If you're not VAT registered, you still need: The word 'Invoice' clearly at the top A unique invoice number Your name and address (or business name) Your customer's name and address The date of the invoice A clear description of the work done The amount charged Payment terms (e.g. due within 14 days) What If You're VAT Registered? If you're VAT registered you need a VAT invoice which includes all of the above plus: Your VAT registration number The VAT rate applied to each item The VAT amount charged The total excluding VAT The total including VAT If you're in construction and your customer is also VAT registered, you may need to apply the VAT reverse charge instead — meaning you don't charge VAT at all and the customer accounts for it themselves.

What About CIS Invoices?

If your customer deducts CIS, your invoice needs to clearly show the split between labour and materials so the deduction is calculated correctly. The deduction only applies to labour — not materials, not VAT. A properly laid out CIS invoice shows: Labour subtotal Materials subtotal CIS deduction (labour x rate) Amount due after deduction Payment Terms — What Should You Use? Standard payment terms for tradespeople are 14 or 30 days. Shorter is better for cash flow. Some lads go to 7 days for smaller domestic jobs. Whatever you choose, put it in writing on every invoice. You're also legally entitled to charge statutory interest on late payments under the Late Payment of Commercial Debts Act. Most tradespeople don't bother, but knowing your rights doesn't hurt.

Common Invoice Mistakes That Delay Payment

No invoice number — makes it hard to track and dispute Vague descriptions like 'work carried out' — always be specific Wrong customer name or address — gives them an excuse to query it No payment terms — they'll take as long as they want Sending it weeks after the job — makes it look unprofessional WhatsApp invoices with no proper format — some customers won't even process these The Fastest Way to Invoice Properly The lads who get paid fastest are the ones who invoice on the same day as the job, send it professionally and follow up without apology. Every day you wait to send an invoice is another day added to when you get paid. Dayrates lets you create a fully compliant invoice from your phone in under 60 seconds — with your business details pre-filled, CIS calculated automatically and a PDF sent straight to your customer. Try Dayrates free for 14 days at dayrates.online — no credit card needed.

Final Thoughts

A good invoice is a professional invoice. It shows the customer you run a proper business, it protects you in any dispute and it removes every excuse for late payment. Get into the habit of invoicing the same day as the job and you'll notice the difference in how quickly the money lands.