How to invoice a client for freelance work
The short answer
A freelance invoice needs your details, the client's details, a unique invoice number, the invoice date, a clear description of the work and when you did it, the amount for each item, any tax, the total, and a due date with how to pay you. Send it as a PDF as soon as the work (or the agreed milestone) is done, put the exact due date on it rather than just "net 30", and follow up the day after it's due.
On this page
What every freelance invoice needs
The UK government publishes the clearest official list, and it's a good checklist wherever you work. An invoice must include:
- a unique identification number,
- your name or business name, address and contact details,
- the client's company name and address,
- a clear description of what you're charging for,
- the date the work was done (the supply date) and the date of the invoice,
- the amount for each item, any VAT or sales tax, and the total amount owed.
In the UK, a sole trader must also show their own name alongside any business name, and an address where legal documents can be delivered. Limited companies must use the full registered company name.
The US has no single federal invoice format, but the same items are standard, and the IRS lists invoices among the documents that support your gross receipts, so keep a copy of every one you send.
Two more things aren't legally required but make a big difference to how fast you're paid: a due date and how to pay (bank details, a payment link, or both).
A worked example
Here is what the body of a simple freelance invoice looks like for a designer billing a website project:
| Description | Quantity | Rate | Amount |
|---|---|---|---|
| Homepage design, two rounds of revisions (1–12 Sept 2026) | 1 | $1,200 | $1,200 |
| Additional page templates | 3 | $250 | $750 |
| Stock photo licences (at cost) | 4 | $15 | $60 |
| Total due | $2,010 |
Above the table go the header details:
- Invoice 2026-014, dated 28 September 2026
- From: your name, business name, address, email
- Bill to: the client's company name, address and the contact who approves invoices
- Due: 28 October 2026 (net 30)
- Pay by: bank transfer to the account shown, or the payment link
Describe the work so someone in the client's accounts team, who wasn't part of the project, can match it to a purchase order or contract. "Design work" gets queried. "Homepage design, two rounds of revisions (1–12 Sept)" gets paid.
How to number your invoices
Each invoice needs a number that's never been used before. The simplest system that never breaks is year plus a running number: 2026-001, 2026-002, and so on. Some freelancers add a client code (2026-ACME-003) to make searching easier.
Rules worth keeping:
- Never reuse a number, even for a cancelled invoice. Mark it cancelled and issue a new one.
- Don't restart numbering per client. Use one sequence for the whole business.
- Avoid starting at 001 if it bothers you, but don't skip numbers randomly either: a gap-free sequence is easy to account for.
Payment terms that actually get you paid
"Net 30" means the full amount is due 30 days after the invoice date. It's common, but vague terms get paid late. Three habits help:
- Write the actual date. "Due 28 October 2026" leaves nothing to interpret. Our guide to net 30 payment terms explains how the days are counted.
- Agree the terms before you start. Put them in the contract or the proposal, then repeat them on every invoice.
- Know your late-payment rights. In the UK, if no date is agreed, payment from one business to another is legally late 30 days after the invoice, and you can claim statutory interest of 8% plus the Bank of England base rate, plus a fixed sum for recovery costs. In the US, late fees depend on your contract and state law, so put any late fee in your agreement upfront.
When to send the invoice
- Small jobs: as soon as the work is delivered.
- Larger projects: split into milestones, such as a deposit to start, a payment at a halfway point and the balance on delivery. A deposit also filters out clients who were never going to pay.
- Ongoing work: on the same day each month, covering the previous month.
The longer you wait to invoice, the longer you wait to be paid. The due date only starts counting once the invoice exists.
Sending it and following up
Send the invoice as a PDF, addressed to the person who pays invoices (not only your project contact), with the invoice number and amount in the subject line: *Invoice 2026-014 from Jane Smith Design, $2,010, due 28 Oct*.
Then follow up on a schedule rather than when you remember:
- A friendly reminder a few days before the due date.
- A reminder the day after it's due, with the invoice attached again.
- A firmer reminder a week or two later, restating the terms and any late-payment interest you're entitled to.
US freelancers: W-9 and 1099-NEC
US clients often ask new freelancers for a Form W-9, which gives them your taxpayer identification number. That's so they can report what they pay you. For payments made from 2026 onwards, a business files a Form 1099-NEC when it pays a non-employee $2,000 or more in a year, up from $600 before. Payments to corporations are generally exempt. Your income is taxable either way, whether or not you receive a 1099.
Send your next invoice in two minutes
InvoicePilot fills in the numbering, dates, tax and totals for you, sends the invoice as a PDF, and reminds the client when it's overdue. Free plan, no card required.
Create an invoice freeFrequently asked questions
Do I need a registered business to send an invoice?
No. Anyone who's done paid work can invoice for it. In the UK a sole trader includes their own name, plus any business name they trade under. In the US you can invoice under your own name and give the client a W-9 with your Social Security number or an EIN.
What's the difference between an invoice and a receipt?
An invoice asks for payment. A receipt confirms that payment has been made. Many freelancers send an invoice first and a receipt, or a "paid" copy of the invoice, once the money arrives.
Can I charge a late fee?
In the UK, businesses can claim statutory interest and a fixed recovery sum on late business-to-business payments even without a clause. In the US it depends on your contract and your state's law, so agree any late fee in writing before the work starts.
Should I charge VAT or sales tax?
In the UK you charge VAT only if you're VAT registered, and then you need a VAT invoice with extra details. In the US, whether services are subject to sales tax varies by state and by the type of service, so check your state's rules.
How soon should I invoice after finishing the work?
The same day, if you can. Payment terms count from the invoice date, so every day you delay invoicing is a day added to when you get paid.
Sources
This is general information, not legal or tax advice. Invoice and tax rules differ by country and state; check with your tax authority or an accountant for your situation.