What you need before you start
Before you write a single line, gather the information an invoice depends on. Having it ready turns invoicing into a two-minute job instead of a back-and-forth with your client.
- Your business details
- Your trading name, address, contact email, and any registration or tax number that applies to you.
- Your client’s details
- The name and address to bill, and their tax number if they are a registered business, which matters for cross-border sales.
- What you are billing for
- A short description of each product or service, with the quantity and the price per unit.
- The tax that applies
- The VAT or sales-tax rate for each line, or a note if the sale is zero-rated, exempt, or reverse charge.
- Dates and terms
- The date you are issuing the invoice and the date payment is due (for example 14 or 30 days later).
- How you want to be paid
- Your bank account or IBAN, or a payment link, so the client can settle without asking how.
How to make an invoice in seven steps
Every invoice, whether handwritten or generated, follows the same shape. Work through these steps in order and you will end up with a complete, professional document.
- 1. Add a header
- Put the word Invoice at the top, along with your business name and logo if you have one, so the document is instantly recognisable.
- 2. Add your details and the client’s
- List your name, address and tax number, then the client you are billing. Both parties must be clearly identified.
- 3. Give it a number and dates
- Assign a unique, sequential invoice number and set the issue date and the payment due date.
- 4. List the line items
- One row per product or service: description, quantity, unit price, and the line total.
- 5. Add tax and totals
- Sum the lines to a subtotal, add VAT or sales tax where it applies, and show the final amount due.
- 6. Add payment details and terms
- Show how and by when to pay: bank details or a payment link, plus any late-payment terms.
- 7. Save it as a PDF and send it
- Export a PDF (so the layout cannot be altered) and email it to your client, keeping a copy for your records.
What every invoice must include
Some fields are a matter of good practice; others are legally required in most countries. A complete invoice carries the word Invoice, a unique invoice number, the issue date, your name and address, your client’s name and address, a description of the goods or services, the amount due, and the tax shown separately where it applies.
If you are registered for VAT or an equivalent tax, you usually must also show your tax number, the tax rate and amount for each line, and in the EU often the client’s VAT number on cross-border business sales. Getting these right is what makes an invoice valid for your client to reclaim tax and for you to keep clean books.
How to calculate totals and tax
The arithmetic is simple. For each line, multiply the quantity by the unit price to get the line total. Add the line totals together to get the subtotal (the amount before tax). Then apply tax: multiply the subtotal, or each line, by the relevant rate to get the tax amount, and add it to reach the total due.
If you sell at more than one tax rate, group the lines by rate and show each rate’s tax separately, so the breakdown is clear. Cross-border sales between EU businesses are often reverse charge: you show the net amount with no VAT and add a note that the buyer accounts for the tax. A tool that knows these rules calculates the totals and the right notes for you, which removes the most common source of invoice errors.
Invoice numbers and dates
Give every invoice a unique, sequential number with no gaps, such as INV-0001, INV-0002, and so on. A consistent series keeps your records easy to follow and is expected by most tax authorities; gaps or duplicates raise questions you do not want.
Show two dates clearly: the issue date (when you raise the invoice) and the due date (when payment is expected). Rather than writing “due on receipt,” state a concrete term such as 14 or 30 days from the issue date. A specific due date is easier to chase and gets you paid faster.
How to send your invoice and get paid
Send the invoice as a PDF so the layout and totals cannot be changed in transit, and keep a copy for your records. Email is fine for most freelancers and small businesses; attach the PDF and write a short, friendly message with the amount and the due date.
Make paying easy. Include your bank details or a payment link directly on the invoice so the client does not have to ask. Invoices that offer an obvious way to pay are settled noticeably faster. If the due date passes, a polite reminder a few days later is normal and usually all it takes.
Common mistakes to avoid
Most invoice problems come from a handful of avoidable slips. A quick check before you send saves awkward corrections later.
- A missing or duplicate number
- Reusing a number or skipping the series makes your records hard to reconcile and can flag a tax review.
- No clear due date
- “Due on receipt” is vague. A specific date sets the expectation and makes follow-up straightforward.
- Wrong or missing tax
- Charging the wrong rate, or forgetting a reverse-charge note on a cross-border sale, makes the invoice non-compliant.
- Vague line descriptions
- A line that just says “services” invites questions. Describe what you delivered so the client can approve it quickly.
- No payment details
- If the client cannot see how to pay, they will not, at least not on time. Always show bank details or a link.
- Sending an editable file
- A word-processor or spreadsheet file can be altered. Always send a PDF.
Frequently asked questions
Do I need software to make an invoice?
No. You can make an invoice in a word processor or spreadsheet, or even by hand. Software helps with sequential numbering, automatic totals and tax, and a clean PDF, but it is not required. You can also use a free online generator with no account, like the one on this page.
What information must an invoice include?
At minimum: the word Invoice, a unique invoice number, the issue date, your name and address, your client’s name and address, a description of the goods or services, the amount due, and the tax (such as VAT) shown separately where it applies. Many countries add specific requirements, such as a VAT number for registered businesses.
How should I number my invoices?
Use a unique, sequential number for every invoice, with no gaps, for example INV-0001 then INV-0002. A consistent series makes your records easy to follow and is expected by most tax authorities.
Do I have to charge VAT or sales tax?
It depends on where you are based, whether you are registered, and where your client is. If you are VAT-registered you usually charge VAT and show your VAT number; cross-border sales between EU businesses often use reverse charge. Check the rules for your country.
Can I make an invoice for free?
Yes. You can create and download a professional invoice for free, with no account and no watermark, using the generator on this page. Nothing you enter is stored.