How to Write Your First Invoice as a UK Freelancer
A step-by-step guide to creating professional invoices, with a breakdown of what's legally required and a free template to download.
Sending your first invoice is one of those milestones that makes freelancing feel real. You have done the work, the client is happy, and now you need to get paid. But staring at a blank document and wondering what to include can be surprisingly daunting. Get it wrong and you risk looking unprofessional, delaying payment, or even falling foul of HMRC requirements.
The good news is that invoicing is not complicated once you understand what is required. This guide walks you through every element of a proper UK freelancer invoice, explains the legal requirements, and helps you set up a system that keeps cash flowing smoothly from day one.
What Must Appear on a UK Invoice
While there is no single legally mandated invoice format in the UK, HMRC and general business practice require certain pieces of information. Missing any of these can give clients an excuse to delay payment or cause problems with your tax records.
Your Business Details
At the top of every invoice, include your full name or trading name. If you operate under a business name that is different from your legal name, include both. For example, “Jane Smith trading as Bright Copy Studio.” You must also include your contact address. This does not have to be your home address if you use a registered business address, but it must be a real postal address.
A Unique Invoice Number
Every invoice needs a unique sequential number. This is not optional — HMRC requires it for your records, and it helps both you and your client track payments. Your numbering system can be simple. Many freelancers start with INV-001 and count upward. Others prefer a date-based system such as 2026-02-001 (year-month-sequence). Whatever system you choose, stick with it consistently and never reuse a number.
The Invoice Date and Due Date
Include the date you issue the invoice and the date by which payment is due. The due date depends on your payment terms, which we will cover shortly. Being explicit about both dates removes ambiguity and sets a clear expectation.
Your Client’s Details
Include the client’s full business name, contact name if applicable, and their address. For larger companies, you may also want to include a purchase order (PO) number if they provided one. Many corporate accounts departments will reject invoices that lack a PO reference, so always ask new clients whether they require one.
A Clear Description of Work
This is where many new freelancers fall short. Do not simply write “copywriting” or “design work.” Be specific. Break down what you delivered, including dates if relevant. For example:
- Website homepage copy (1,200 words) — delivered 28 January 2026
- Three blog articles (800 words each) — delivered 3 February 2026
- Two rounds of revisions — completed 5 February 2026
Specific descriptions make it harder for clients to query the invoice and easier for you to reference the work if any dispute arises later.
The Amount Due
State each line item’s cost and provide a clear total at the bottom. If you are not VAT registered, you do not need to show VAT. Simply state the total amount due. If you are VAT registered, you must show the net amount, the VAT amount, and the gross total separately.
Your Payment Details
Include your bank account details so the client can pay by bank transfer, which is the standard method for UK business payments. At a minimum, provide your account name, sort code, and account number. If you work with international clients, include your IBAN and BIC/SWIFT codes as well.
Payment Terms
State your payment terms clearly on the invoice. “Payment due within 30 days of invoice date” is the most common standard, but you can set whatever terms you agree with your client.
VAT: When You Need to Worry About It
If your taxable turnover is below the VAT registration threshold — currently £90,000 per year — you do not need to register for VAT and should not charge it on your invoices. If you are not VAT registered, do not include a VAT number or VAT breakdown. Simply invoice for the net amount.
Once your turnover exceeds or is expected to exceed £90,000 in any rolling 12-month period, you must register for VAT with HMRC. After registration, your invoices become “VAT invoices” and must include additional information:
- Your VAT registration number
- The VAT rate applied to each item (usually 20% standard rate)
- The net amount, VAT amount, and gross total for each line
- The total VAT charged on the invoice
Some freelancers choose to register voluntarily before reaching the threshold, particularly if most of their clients are VAT-registered businesses that can reclaim the VAT. This can also allow you to reclaim VAT on your own business expenses. However, if your clients are mainly consumers or small businesses that cannot reclaim VAT, voluntary registration effectively increases your prices by 20%.
Setting Up an Invoice Numbering System
A good numbering system is simple, sequential, and easy to search. Here are three approaches that work well:
Simple sequential: INV-001, INV-002, INV-003. Straightforward and works perfectly for most freelancers.
Date-based: 202602-001, 202602-002. The prefix tells you the month and year at a glance, which is helpful when reviewing your records at tax time.
Client-coded: ACME-001, ACME-002 for Acme Corp, then BETA-001 for Beta Ltd. This is useful if you work with a small number of regular clients and want to quickly see all invoices for a particular client.
Whichever system you use, keep a simple spreadsheet or use invoicing software to track your numbers. Gaps in your invoice sequence can raise questions during an HMRC enquiry, so if you void an invoice, keep a record noting why rather than deleting it entirely.
Choosing Your Payment Terms
“Net 30” — meaning payment is due 30 days after the invoice date — is the standard in UK business. However, as a freelancer you have the right to set whatever terms you like, and there are good reasons to negotiate shorter windows.
Net 14 is increasingly common among freelancers and small agencies. It keeps your cash flow healthier and is perfectly reasonable for most projects.
Payment on receipt is appropriate for smaller one-off jobs, particularly with new clients. It signals that you expect prompt payment and avoids the long wait that Net 30 can become in practice.
Milestone payments work well for larger projects. You might invoice 50% upfront before starting, 25% at the midpoint, and the final 25% on completion. This reduces your risk and helps fund the time you invest in the project.
Whatever terms you choose, agree them with the client before starting work and confirm them in writing — ideally in your contract or statement of work.
A Walkthrough: Your First Invoice
Let us put it all together. Here is what a complete freelancer invoice looks like in practice:
Header area: Your name or business name, your address, your email, and your phone number. Optionally, your logo.
Invoice details: Invoice number: INV-001. Invoice date: 8 February 2026. Due date: 8 March 2026. Payment terms: Net 30.
Client details: Client company name, contact person, client address, and PO number if applicable.
Line items:
| Description | Quantity | Rate | Amount |
|---|---|---|---|
| Brand strategy workshop (half day) | 1 | £600.00 | £600.00 |
| Logo design including three concepts and two rounds of revisions | 1 | £1,200.00 | £1,200.00 |
| Business card design (double-sided) | 1 | £200.00 | £200.00 |
Total: £2,000.00
Payment details: Bank: Starling Bank. Account name: J. Smith. Sort code: 60-83-71. Account number: 12345678.
Footer note: “Thank you for your business. Please quote invoice number INV-001 as your payment reference.”
Common Invoicing Mistakes to Avoid
Forgetting to include payment details. It sounds obvious, but many new freelancers send invoices without bank details, forcing the client to chase you for the information and delaying the entire process.
Vague descriptions. “Design work — £500” tells the client nothing and invites queries. Be specific about what you delivered.
Not setting clear payment terms. If you do not state when payment is due, the client has no deadline. Always include explicit terms.
Invoicing the wrong entity. Larger businesses may have multiple subsidiaries or departments. Make sure you are invoicing the correct legal entity as specified by your client’s accounts team.
Inconsistent numbering. Skipping numbers, reusing them, or switching systems mid-year creates confusion in your records and can cause problems with HMRC.
Waiting too long to invoice. Send your invoice as soon as the work is complete or the milestone is reached. The longer you wait, the longer it takes to get paid, and the less urgency the client feels.
Invoicing Software Worth Considering
While you can create invoices in a Word document or spreadsheet, dedicated invoicing software saves significant time and keeps your records organised automatically.
FreeAgent is one of the most popular choices for UK freelancers and sole traders. It handles invoicing, expenses, Self Assessment tax estimates, and bank reconciliation. Plans start from around £14.50 per month, and many UK banks (including NatWest, Mettle, and Starling) offer it free to business account holders.
Xero is a powerful option that scales well if you expect your business to grow. It offers excellent invoicing, multi-currency support, and a vast library of integrations. The Starter plan begins at £15 per month.
Wave is a free invoicing and accounting tool that works well for freelancers who are just starting out and want to keep costs down. It covers basic invoicing and receipt scanning without charge, though it lacks some of the advanced features of paid alternatives.
QuickBooks Self-Employed is another solid choice, particularly if you want help tracking mileage and separating personal and business expenses. It often runs promotional pricing for the first few months.
All four options let you send invoices directly to clients by email, set up automatic payment reminders, and track which invoices are outstanding — features that make a real difference to your cash flow.
Building Good Invoicing Habits
The freelancers who get paid reliably are not necessarily the ones with the fanciest invoices. They are the ones who invoice promptly, follow up consistently, and keep clean records. Set aside time each week — even just 15 minutes on a Friday — to send any outstanding invoices and chase any that are overdue.
Your first invoice might feel like a small thing, but getting it right sets the tone for your entire client relationship. A clear, professional invoice tells your client that you take your business seriously, and it makes their accounts team’s job easier — which is ultimately what gets you paid on time.
