TidyToolsWhat makes an invoice count
An invoice is not just a request for money — in most countries it's the document that has to survive an accountant, and occasionally a tax inspector. The things that make it valid are dull and specific, and leaving one out is the usual reason a client's finance department sends it back rather than paying it.
- The word "Invoice". Sounds trivial; it's often a formal requirement, and it's what separates your document from a quote or a receipt.
- A unique, sequential number. Every invoice you ever issue needs its own, and the sequence shouldn't have gaps. This is the part most people get wrong when they start out.
- The date it was issued, and the date payment is due. "Due on receipt" is a real answer, but a specific date is chased more easily.
- Both parties in full. Your trading name and address, and the client's — the actual registered entity, not just the name of the person who hired you.
- A clear description of the work, itemised. "Design work — £3,000" invites questions. Three lines with days and rates does not.
- The tax position. If you charge VAT, GST or sales tax, the rate and the amount have to be shown separately from the net figure, along with your registration number.
- How to actually pay you. An astonishing number of unpaid invoices are unpaid because the bank details weren't on them.
Numbering, and why gaps cause trouble
Pick a scheme and never break it: INV-001, INV-002, or a year prefix like 2026-014. If an invoice is wrong, don't delete it — issue a credit note or a corrected invoice with a new number. A missing number in a sequence looks, to anyone auditing you, exactly like an invoice you were paid for and hid.
Dates are what you'll argue about
The issue date starts the clock, and in several tax systems it determines which period the income falls into — invoicing on 31 March rather than 1 April can move the whole amount into a different tax year. Send it promptly and date it honestly.
This tool writes dates as 6 Aug 2026 rather than in figures on purpose. 06/08/2026 means August in Britain and June in the United States, and that ambiguity has caused more than one payment to arrive a month late.
Getting paid, not just invoiced
The unglamorous truth is that most late payment isn't refusal, it's friction. An invoice that arrives on a Friday afternoon addressed to the wrong entity, with no PO number and no bank details, doesn't get refused — it gets set aside, and nobody picks it up again.
So: ask at the start of the job who invoices should be addressed to and whether they need a purchase order number, because large companies frequently won't pay without one. Send it the day the work is delivered, while you're still fresh in everyone's mind. Put the invoice number in the email subject. And if you're quoting a rate before any of this, our salary to freelance rate calculator and rate increase calculator exist for that argument.
Billing hourly? The timesheet to invoice calculator turns tracked hours into the line totals you can paste straight in here. And when the money lands, remember that a slice of it isn't yours — the tax set-aside calculator works out how much to move out of reach.
Frequently asked questions
Is any of this uploaded anywhere?
No. The form, the totals and the PDF are all built by JavaScript running on this page. Your client's name, your address and your bank details never leave your device — there is no server here to receive them. You can load the page, disconnect from the internet, and still produce the PDF.
Is there a watermark or a limit?
Neither. The PDF is a plain document with nothing added to it, and you can make as many as you like. There's no free tier to run out of, because there is no paid tier.
Will my details still be here tomorrow?
Only if you tick "Remember my details on this device". That stores your own business details, currency and payment notes in this browser's local storage — on your machine, not ours. The client details and the amounts are never saved, so each invoice starts clean. Untick the box and the saved copy is erased immediately.
Can I add my logo?
Yes, PNG or JPG. It's read in your browser, scaled to fit, and embedded into the PDF. Transparent backgrounds come out white, since PDF images have no transparency here — if your logo is white-on-transparent, export a version with a solid background first.
Do I need to charge VAT or sales tax?
That depends on where you are, what you sell and how much you turn over, and it genuinely varies country by country — so this tool asks rather than assumes. Set the rate to 0 if it doesn't apply to you. If you're registered, your registration number belongs on the invoice too; there's a field for it.
Can I edit the PDF afterwards?
Not directly, and you shouldn't need to — change the form and download it again. An invoice you've already sent should never be quietly edited anyway; issue a corrected one with a new number so the paper trail stays honest.
What if I have more line items than fit on a page?
It carries on to a second page, and a third, with the column headings repeated. The totals always sit at the end.
Is this legal advice?
No. It's a well-formed invoice that includes the fields commonly required, but the rules differ by country and by what you do. If you're unsure whether you must register for VAT, or what your invoices legally have to show, ask an accountant in your own jurisdiction.