A simple invoice needs eight things: the word Invoice, an invoice number, the date, your details, your client's details, what you are charging for, the total, and how and when to pay. That is enough for most small jobs, and it fits on half a page.
Below you will find each field explained, a filled-in example that shows what an invoice looks like, and a clear line for when a simple invoice is not enough. If you want the long version, see what to include on an invoice.
Short on time? Skip ahead: Open the free invoice generator
What an invoice looks like
An invoice is a one-page document. At the top, it says who it is from and that it is an invoice. In the middle, a short list shows what you did and what it costs. At the bottom, there is a total and a line telling the client how to pay.
That is all. Most invoices that feel complicated are simple ones with extra decoration. If you can write a clear note that says "I did this, it costs that, please pay by this date", you can make an invoice.
The 8 fields of a simple invoice
- The word "Invoice" at the top, so nobody mistakes it for a quote or a receipt.
- An invoice number that is unique, such as 001 or INV-0001. See invoice numbering if you want a system.
- The issue date, written clearly, such as Oct 28, 2026.
- Your name or business name, with an address and an email or phone number.
- Your client's name or business name, and their address or email.
- A description of the work or goods, with quantity and price for each line.
- The total amount due, in the currency you agreed on. Dollars here, but it works the same in pounds.
- Payment details and the due date: how to pay (bank transfer, ACH or card) and by when.
A filled-in simple invoice
Copy this layout into any tool, or into a blank document, and replace the details with your own.
INVOICE 001
Date: Oct 28, 2026
From: Maya Chen, Web Design, [email protected], 14 Pine Road, Denver CO
To: Blue Door Yoga, [email protected]
Website update, 6 hours at $60.00 $360.00
Contact form setup, 1 at $90.00 $90.00
Total due $450.00
Due: Nov 11, 2026
Pay by bank transfer or ACH. Reference: Invoice 001
Fill in each field well
Be specific in the description. "Web design" makes the client wonder; "Website update, 6 hours at $60.00" answers the question before it is asked. One line per task or product is the easiest to read.
Always give a due date, not just "pay soon". If you have no set terms, "due in 14 days" is a safe default for a small job. Our guide to Net 30 and payment terms explains the usual options.
Put your payment details on the invoice itself. The fewer messages a client has to send you to find out where the money goes, the sooner it arrives.
Three ways to make it
Whichever you use, send the invoice as a PDF so that the layout stays as you made it.
- In a blank document: type the eight fields in order and save it as a PDF. Fine once; tiresome by the tenth invoice.
- With a template: start from a layout that is already set out. See the invoice templates.
- With a generator: the free invoice generator has a field for each item above, does the maths and gives you a PDF without an account.
When a simple invoice is not enough
Eight fields cover a small job for a client in your own country. Add more when any of these apply.
| Situation | What to add |
|---|---|
| You charge sales tax | The tax rate, the tax amount and your tax ID. Check your state's rules or ask your accountant. |
| The client uses purchase orders | The PO number, or the invoice may be rejected |
| You received a deposit | The deposit as a deduction, and the remaining balance |
| A business client needs it for its books | Their full legal name and billing address, plus your tax ID |
| A client abroad | The currency, and payment details that work internationally |
| Ongoing or monthly work | The billing period covered |
| You want to charge for late payment | Your late fee terms, stated before the work. See late fees |
Mistakes even simple invoices make
- No invoice number, or two invoices with the same one.
- No due date.
- Your own contact details missing, so the client cannot reply.
- A total that does not match the lines. Add it twice.
- Mixing hours and a flat fee in one line without saying which.
- Sending a file the client cannot open. A PDF opens everywhere.
From simple to professional, when you are ready
You can start simple and add polish as you grow: a logo, saved clients, automatic numbers and reminders. The Jiffy app does that, and the free plan covers three invoices a month. Until then, the free generator is all you need.
When you outgrow the basics, the full step-by-step is in how to write an invoice.