Legal minimums (most countries)
- Sequential, unique invoice numbers
- Your registered business name and address
- Tax ID / VAT number when registered
- Issue date and due date
- Buyer's name and address
- Itemized description, quantity, price, tax rate, total
Cash vs accrual timing
If you account for tax on cash received, the invoice date matters less than the payment date; on accrual, tax is due when the invoice is issued. Confirm which regime you are in before numbering heavily.
The weekly invoicing habit
Pick one slot (Friday afternoon) to issue everything from that week. Batching reduces mistakes, makes chasing predictable and keeps the sequence gap-free.
Frequently Asked Questions
How long must I keep invoices?
Commonly 5–10 years depending on jurisdiction — check your local tax authority. PDFs from the generator are fine as long as they are legible and numbered.
Do I need software to invoice legally?
No. A compliant invoice on paper or PDF is valid; software is convenience, not a legal requirement in most places.