Guide to freelancer invoicing in the UK

If you’re freelancing in the UK, getting your invoicing right isn’t just about looking professional - it’s about getting paid faster, staying HMRC-compliant, and keeping your finances stress-free at tax time.

Whether you’re new to freelancing or looking to tidy up your process, this guide covers everything you need to know to issue clean, compliant, and efficient invoices - and how tools like Quivva can make it effortless.

Why invoicing matters

A well-prepared invoice builds trust and speeds up payment.
A sloppy one causes confusion, delays, and even HMRC issues.

When you send a professional invoice:

• Clients take you seriously.
• You get paid faster.
• You stay compliant and organised for tax time.
• With subtle design cues they can help build your personal brand.

That’s why Quivva makes every invoice look sharp, compliant, and consistent - automatically.

What HMRC wants to see on a UK invoice

Here’s what HM Revenue & Customs (HMRC) expects to see:

If you’re registered for VAT:

• Clearly state “VAT Invoice”
• Your business name and address
• Your VAT Registration Number
• Invoice date and Tax point (time of supply) if different
• Description of goods or services
• Quantity and price excluding VAT
• VAT rate and total VAT amount
• Total amount due
• Invoice number
• Client’s name and address

If you’re not registered for VAT:

• Title your document “Invoice”
• Include your business name and address
• Invoice date
• Invoice number
• Description of work
• Total amount due
• Do not charge or show VAT

💡 Quivva automatically formats invoices to meet HMRC standards - no template tweaking required.

Choosing an invoice number format

Each invoice must have a unique reference number - this helps you, your clients and HMRC keep records tidy.

• Keep it sequential, e.g. INV-001, INV-002, etc.
• Gaps are fine; you’re not breaking any law if some numbers are skipped, but sequences are preferred.
• Avoid per-client numbering - it gets confusing.
• Best practice: a global sequence for your business.

Quivva handles numbering automatically, ensuring every invoice is unique and compliant.

Setting Payment Terms

Payment terms set expectations and help you maintain cash flow.

• Standard terms: 7, 14, or 30 days
• For new clients or one-off projects: consider 50% upfront
• Always include:
  • A clear due date
  • Accepted payment methods (bank transfer, BACS, card)
  • A note on late fees (under the Late Payment of Commercial Debts Act)

You can also include a friendly footer like:

Thanks for your business - prompt payment is appreciated!

Following Up on Late Payments

Late payments happen - but a consistent follow-up system makes all the difference.

Example timeline:

• Day after due date: Friendly reminder - “Just checking this hasn’t slipped through.”
• 7 days late: Send a copy of the invoice with a payment link.
• 14 days late: Mention your late fee policy or pause work until paid.

Stay polite but firm.

Record-Keeping and HMRC Compliance

HMRC requires you to keep business records for at least 5 years after the 31 January submission deadline of the relevant tax year. That includes:

• Paid and unpaid invoices
• Matching invoice dates with your accounting records
• Backups in case of audit

Quivva keeps everything securely in the cloud, so you can find any invoice in seconds - no digging through folders or spreadsheets.

When and How to Charge VAT

If your taxable turnover exceeds £90,000 (last updated {{ post.publishDate }}), you must register for VAT.

Once registered:

• Add 20% VAT (standard rate) to taxable invoices
• Submit your VAT Return quarterly (Making Tax Digital compliant)
• Clearly show VAT on each invoice

If you’re under the threshold, registration is optional. You might choose to register voluntarily if your clients are VAT-registered businesses (so they can reclaim it) or if you have high VAT-able expenses.

Quivva simplifies VAT and helps you prepare for your returns.

Branding and styling

Invoices are admin tasks for your client at the end of the day. So don’t go crazy with templates. The best solution is a standard template that is easy to read and follows conventions and best practices.

But some subtle design nods to your business - such as your logo and accent colour - can help build that all important personal brand.

Quivva keeps this simple, all you need to do is upload your business logo.

Best Practices for Professional Invoices

Looking professional doesn’t mean looking corporate. Keep it clean, simple, and consistent.

• Use your business name, logo, and colours
• Avoid jargon in your descriptions
• Send invoices immediately after completing work
• Include your UTR (if sole trader) or Company Number (if Ltd)

You can save a huge amount of time by using a system that remembers your details and client preferences - like Quivva does automatically.

How Quivva Simplifies It All

Here’s how Quivva makes invoicing (and everything around it) simple:

• Automatically creates HMRC-compliant invoices
• Adds your logo and branding
• Tracks paid and unpaid invoices
• Links your time tracking directly to your invoices