Guide
How to Write an Invoice
Published June 5, 2026 · 8 min read
You did the work. Now you need to get paid. That's where the invoice comes in.
An invoice is just a document that says "here's what I did, here's what it costs, and here's how to pay me." It doesn't need to be fancy. But it does need to include certain things, or your client might kick it back — or worse, sit on it because something's unclear.
This guide walks you through what to put on an invoice, how to structure it, and what not to do. If you want to skip the reading and just make one, open the generator and fill in the form.
What goes on an invoice
Every invoice needs these things. Leave any of them out and you're making it harder for your client to pay you.
1. Your name (or business name) and contact info
Put your full name or business name at the top. Add your email address and at least one other way to reach you — phone number, mailing address, or both. If you have a business registration number, include that too.
2. Your client's name and contact info
Who's paying you? Put their name (or company name) and billing address. This matters more than people think — if the invoice doesn't clearly say who it's for, the client's accounts payable team might not process it.
3. An invoice number
Pick a numbering system and stick with it. Start with 001, or use a format like 2026-042 (year + sequence). The point is that each invoice has a unique number so you and your client can reference it later. Don't skip numbers. Don't reuse them.
4. Dates
Two dates matter:
- Issue date — when you send the invoice
- Due date — when you expect payment
A common setup is "issued June 1, due June 30" — giving the client 30 days. But you can set any terms you agreed on.
5. What you're billing for
Each line should describe the work, the quantity (hours, units, sessions), and the rate. For example:
- Website redesign — 40 hours × $75/hr
- Logo design — 1 project × $1,500
- Monthly retainer — June 2026 — $2,000
Be specific enough that the client can match this to the work you did. "Consulting" with a big number next to it is a red flag for most clients (and their accountants).
6. The total
Add up the line items. If you need to charge tax, add it on a separate line (don't hide it in the total). Show the subtotal, the tax, and the final amount.
7. How you want to get paid
Tell the client exactly how to pay. Bank transfer? Include your bank name, account number, and routing number (or IBAN). PayPal? Include the email. Don't make the client guess — every extra step they take is a delay.
A quick example
Here's what a simple invoice looks like with all the pieces in place:
┌─────────────────────────────────────────────┐ │ INVOICE #2026-003 │ │ │ │ From: Sarah Chen │ │ sarah@example.com │ │ 555-012-3456 │ │ │ │ To: Acme Corp │ │ 123 Business Ave, Suite 400 │ │ New York, NY 10001 │ │ │ │ Date: June 1, 2026 │ │ Due: June 30, 2026 │ │ │ │ ─────────────────────────────────────────── │ │ Website redesign 40 hrs × $75 $3,000 │ │ Content migration 10 hrs × $60 $ 600 │ │ ─────────────────────────────────────────── │ │ Subtotal $3,600 │ │ Tax (8%) $ 288 │ │ ─────────────────────────────────────────── │ │ TOTAL $3,888 │ │ │ │ Pay via bank transfer: │ │ Chase Bank · Acct 123456789 · Routing 021... │ └─────────────────────────────────────────────┘
Common mistakes that slow down payment
I've seen these happen a lot. All of them are easy to fix.
- Missing payment details. You'd be surprised how many people forget this. No payment info = client has to email you to ask = days lost.
- Vague line items. "Services rendered" tells the client nothing. Write what you actually did.
- No due date. Without a due date, the client will pay whenever they feel like it. That might be never.
- Typos in the amount. Check your math before you send. Wrong totals can void the invoice.
- Sending to the wrong person. If the client has an accounts department, make sure you're sending the invoice there — not to your project manager.
How to send your invoice
Email is the standard. Attach a PDF — not a Word doc, not a Google Sheets link. PDFs can't be accidentally edited, and they look the same on every device.
Keep the email short. Something like:
Subject: Invoice #2026-003 — Website Redesign Hi [Client Name], Attached is invoice #2026-003 for the website redesign and content migration work completed in May. Payment is due by June 30, 2026. Let me know if you have any questions. Thanks, [Your Name]
Frequently asked questions
What should I put on my first invoice?
Your name and contact details, the client's name and address, a unique invoice number, the date, a list of what you're billing for with amounts, any tax, and how you want to be paid. That's the minimum.
Do I need to number my invoices?
Yes. Pick a numbering system and stick with it. You can start with 001, or use a format like 2026-001. The number is how you and your client track which invoice is which.
Can I send an invoice without a company?
Yes. Freelancers and sole traders send invoices using their own name. You don't need a registered company to bill someone for work you did.
How do I make an invoice into a PDF?
Use a free invoice generator like InvoiceCraft. Fill in the form, preview your invoice, then click Download PDF. Your browser handles the rest — no software to install.
Make your invoice now
Ready to write one? Open the free invoice generator — no signup, no watermarks, no nonsense. Pick a template that matches your work and fill in the form. You'll have a finished invoice in under 5 minutes.
Written by Allen Wong. If this guide helped you, consider supporting InvoiceCraft on Ko-fi.