How to Write an Invoice UK: Template & Legal Requirements for 2026
Legal Requirements for UK Invoices
Every UK invoice must include the following information to be legally valid:
- Unique invoice number: Sequential (e.g., INV-001, INV-002)
- Your business name and address
- Client name and address
- Invoice date
- Description of goods or services
- Amount charged (excluding VAT)
- VAT amount (if applicable)
- Total amount due
- Payment terms (e.g., Net 30)
- Payment methods accepted
💡 Quick Tip
Thistle generates professional invoices in seconds—automatically compliant with UK and VAT requirements.
VAT Invoice Requirements
If you're VAT-registered, your invoice must also include:
- Your VAT registration number
- VAT rate applied (e.g., 20% standard rate)
- VAT amount for each line item
- Total VAT charged
Invoice Template Example
INVOICE
Invoice Number: INV-001
Invoice Date: 4 February 2026
Due Date: 4 March 2026
From:
Your Business Name
123 Business Street
London, SW1A 1AA
VAT Number: GB123456789
To:
Client Name
456 Client Road
Manchester, M1 1AA
Description Qty Rate Total
-------------------------------------------------------
Website Design 1 £2,500 £2,500.00
Logo Design 1 £500 £500.00
Subtotal: £3,000.00
VAT (20%): £600.00
Total: £3,600.00
Payment Terms: Net 30
Payment Methods: Bank Transfer, Card
Bank Details:
Account Name: Your Business Name
Sort Code: 12-34-56
Account Number: 12345678
Create Professional Invoices in Seconds
Thistle's invoice builder is pre-loaded with UK-compliant templates. Add your logo, customize colors, and send—all in under 60 seconds.
Start Free Trial →Best Practices for Payment Terms
| Payment Term | Meaning | Best For |
|---|---|---|
| Due on receipt | Immediate payment | Small projects, new clients |
| Net 14 | 14 days to pay | Faster cash flow |
| Net 30 | 30 days to pay | Industry standard |
How to Get Paid Faster
- Offer multiple payment methods: Bank transfer, card, PayPal
- Send invoices immediately: Don't wait until month-end
- Include payment links: Make it one-click easy
- Send reminders: Automated follow-ups work
- Offer early payment discounts: 2% off if paid within 7 days
Get Paid 2x Faster with Thistle
Thistle invoices include one-click payment links, automated reminders, and read receipts. Know when your invoice is opened and get paid faster.
Start 7-Day Free TrialFrequently Asked Questions
What must be included on a UK invoice?
A UK invoice must include: unique invoice number, your business name and address, client name and address, invoice date, description of goods/services, amount charged, payment terms, and your contact details.
Do I need to include VAT on my invoice?
Only if you're VAT-registered. If you are, you must include your VAT number, VAT amount for each item, and the total VAT charged.
What payment terms should I use?
Common payment terms are "Net 14" (14 days), "Net 30" (30 days), or "Due on receipt". Shorter terms improve cash flow but may deter some clients.
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