Free Invoice Generator with PDF Download

What a valid invoice needs

An invoice is a legal document, not a note asking to be paid. Most jurisdictions require broadly the same elements, and missing one is the usual reason an invoice sits unpaid in someone's accounts inbox.

• The word "Invoice". Sounds trivial. It distinguishes the document from a quote, a proforma or a statement, and accounts departments route on it.
• A unique, sequential number. Required almost everywhere, and it is what the client will quote when paying.
• The issue date, and separately the date the work was done if they differ.
• Your full name or trading name and address, plus your company registration number if you have one.
• The client's name and address. The legal entity, not just a contact's name.
• A clear description of what was supplied, with quantities and unit prices.
• The amount due, with any tax shown on its own line and the subtotal separate from the total.
• Payment terms and a due date, plus how to pay.

Numbering, and why gaps matter

Invoice numbers must be sequential and unbroken. This is not bureaucratic fussiness: a gap in the sequence is exactly what a deleted invoice looks like, and it is one of the first things an audit checks.

If you void an invoice, do not delete it. Issue a credit note against it and keep both in the sequence. If you make a mistake, the same applies.

Adding the year, as in 2026-014, keeps filing sane and stays sequential within the year. Avoid embedding the client name in the number, because it makes the sequence non-obvious and tells every client roughly how many invoices you have issued.

Payment terms that actually get paid

The single most effective change most freelancers can make is shortening terms. Net 14 is completely standard for small suppliers and gets paid meaningfully faster than net 30, because it lands in an earlier payment run rather than because anyone hurries.

Put the due date on the invoice as an actual date. "Net 30" requires the reader to work out when that is, and nobody does. "Due 3 October 2026" is unambiguous and shows up in a diary.

Other things that measurably help:

• Invoice immediately. The clock starts when you send it, not when the work finished. A week's delay is a week's delay in payment.
• Send it to accounts payable, not your contact. Ask for the right address at the start of the project. Invoices sent to a project manager sit in their inbox.
• Include a purchase order number if they use them. In larger organisations, an invoice without a PO number is frequently unpayable regardless of goodwill.
• Ask for a deposit on larger jobs. Between 25% and 50% up front is normal, filters out clients who were never going to pay, and improves your cash flow more than any collections process.

When an invoice goes unpaid

Chase early and without apology. A polite reminder the day after the due date is completely normal business practice and is very often all it takes, because the most common reason for late payment is that nobody looked at it.

Escalate on a schedule rather than by feeling: a reminder at day one, a firmer note at day seven asking for a payment date, and a formal notice at day fourteen. Keep every message short, factual and free of hedging.

Many countries give suppliers a statutory right to interest and a fixed recovery charge on late commercial payments. In the UK that is 8% above the Bank of England base rate plus a fixed sum per invoice. You do not have to charge it, and mentioning that the right exists is often enough on its own.

Keep your copies

Retention requirements vary but six years is a common minimum, and it applies to what you sent, not what you meant to send. Save the PDF you actually issued, keep them in a single folder named by invoice number, and back that folder up somewhere other than the laptop that generated them.

This tool keeps nothing. Everything is laid out and written to PDF in your browser, which means there is no copy on any server and no copy anywhere else if you do not save the file. That is the trade for not having to hand your client list to a third party.