What is an invoice?
An invoice is a request for payment you send after delivering a product or service. It records what was sold, when, for how much and when payment is due. For you, it's how you get paid and how you keep track of income. For your client, it's the document their accounts team needs to pay you and to claim back tax.
A clear invoice gets paid faster. OZO lays out every required detail for you, so you can focus on the work itself rather than on formatting.
What to put on an invoice
- Your details: business name, address, email and, where relevant, your tax or VAT number.
- Your client's details: who you're billing, with their billing address.
- An invoice number: unique and in sequence (INV-0001, INV-0002…). OZO moves on to the next number automatically.
- Dates: the issue date and the due date. Payment terms like Net 30 make the deadline unmistakable.
- Line items: what you did or sold, the quantity and the rate.
- Totals: subtotal, discount, tax, shipping and the amount due.
- How to pay: bank details or a payment link, plus any late-payment terms.
Tips to get paid on time
- Invoice as soon as the work is done. The longer you wait, the longer you wait to be paid.
- Be specific. "Website redesign: 5 pages, 2 revision rounds" invites fewer questions than "Web work".
- State clear terms. A due date beats "payable on receipt", which many clients read as "whenever".
- Make paying easy. Put your payment details on the invoice itself, not in a separate email.
- Follow up politely. If an invoice is still unpaid after the due date, send a friendly reminder before adding late fees.
Invoice vs estimate
An estimate comes before the work: it tells a client what a job is likely to cost so they can decide whether to go ahead. An invoice comes after: it asks for payment for what was actually delivered. An estimate isn't a bill and usually has an expiry date; an invoice has a due date.
You can write an estimate with the free estimate generator and, once the client accepts, turn it into an invoice in one click, so nothing has to be typed twice.
Invoice templates and related documents
Starting from scratch? Pick a ready-made example: the freelancer invoice template, the contractor invoice template or the consulting invoice template. Once you're paid, turn the invoice into a payment receipt in one click; if you need to reduce it, issue a credit note. Billing before delivery? Send a proforma invoice.
Check the tax on a price with the VAT calculator, and if a client pays late, work out what you can charge with the late payment interest calculator.