AvoHow to Fill Out an Invoice (Step by Step, With Example)
How to fill out an invoice correctly: the 9 fields every invoice needs, what to write in each, a filled example, and the mistakes that get invoices paid late.
The 9 things every invoice needs
- 1. The word “Invoice” and a unique invoice number (2026-001).
- 2. Your business name, address, phone, email, and license or tax ID if your trade requires it.
- 3. The client's name and address, and the person who approves payment.
- 4. Invoice date and due date. Write a real date, not “on receipt”.
- 5. The job or project reference: address, PO number or project name.
- 6. Line items: description, quantity, unit price, amount. One line per thing you did or supplied.
- 7. Subtotal, tax (if any), deposits or credits as negative lines, and the total due.
- 8. Payment terms: Net 15, late fee if any, and how to pay (Zelle, ACH, card link, check).
- 9. A short note: thanks, warranty, or what happens next.
How to write the line items
- Describe the work the way the client remembers it: “Replace kitchen faucet, test for leaks” rather than “plumbing labor”.
- Put quantities and units: hours × rate, feet × price per foot, 4 visits × $45.
- Separate labor from materials. Separate anything added on site from the original quote.
- Show a deposit or retainer you already received as a negative line, so the total is the balance due.
Filled example
A contractor invoice for a garage job. Note the deposit as a negative line and the change order on its own line.
| Description | Qty × rate | Amount |
|---|---|---|
| Demo and haul-away, garage | 1 job | $650.00 |
| Framing labor — 2 carpenters | 16 h × $55.00 | $880.00 |
| Lumber and fasteners (receipts attached) | 1 lot | $1,214.30 |
| Change order #1 — add window header | 1 | $340.00 |
| Deposit received 02 Mar | −$1,000.00 | |
| Total due | $2,084.30 | |
Mistakes that delay payment
- No due date. Invoices without a due date are paid later and are harder to chase.
- One lump-sum line. The client cannot approve what they cannot read.
- Missing PO number for a business client. Accounts payable will reject it.
- No payment method. Every extra step between reading the invoice and paying it costs days.
- Sending it a week later. Invoice the same day, from the job if you can.
Fill it on your iPhone in a minute instead
Avo keeps your clients and your usual line items, so the next invoice is three taps. Your first three documents are free, full-quality PDF, no watermark. Premium from $59.99/year if you invoice often.
Questions
Do I need an invoice number?
Yes. It is how you and the client refer to the invoice, and it is what bookkeeping software and tax preparers expect. Use year plus sequence and never reuse a number.
What's the difference between an invoice and a receipt?
An invoice asks for payment and shows the amount due. A receipt confirms payment was received. After the client pays, send a receipt or mark the invoice paid.
Can I handwrite an invoice?
You can, but a typed PDF is easier to read, easier to file and looks like a business. A fillable PDF template or an invoice app takes the same minute.
Where do I put the tax?
After the subtotal and before the total, as its own line with the rate. If only some lines are taxable, mark them and compute tax on those only.