Guide Nº 02 — FundamentalsLast updated July 24, 2026
How to invoice a client, step by step
To invoice a client, send them a document containing your business details, their details, a unique invoice number, an issue date and due date, line items with rates, the total with tax shown separately, and how to pay. You can build that document from a template, or skip the re-typing entirely by forwarding the client’s email to a service that generates the invoice for you.
The seven fields every invoice needs
- Your business identity — legal/trading name, address, email, and tax/VAT ID if you have one.
- The client’s identity — company name, contact person, and billing address or email.
- A unique invoice number — sequential, no gaps, never reused.
0014beats clever schemes. - Two dates — the issue date, and the due date derived from your payment terms.
- Line items — one row per deliverable: description, quantity, rate, amount. Specific descriptions get paid faster than “services rendered.”
- The total — subtotal, tax as its own line, then the amount due in the agreed currency.
- How to pay — a payment link beats bank details typed into a footer; every extra step your client takes delays payment.
Payment terms, translated
| Term | Meaning | Use when |
|---|---|---|
| Due on receipt | Pay immediately | Small jobs, new clients, deposits |
| Net-15 | Due 15 days after invoice date | Ongoing freelance relationships |
| Net-30 | Due 30 days after invoice date | The B2B default; larger companies expect it |
| 50% upfront | Half before work starts, half on delivery | Projects over a few thousand dollars |
Numbering, records, and the boring parts that save you
Keep one sequence for the life of the business (0001…), store every sent invoice as a PDF, and record three dates per invoice: sent, due, paid. That’s a complete freelance invoicing system — an accountant can reconstruct your year from it, and many jurisdictions expect exactly this: sequential numbers, retained copies, tax shown separately.
On tax:whether you charge sales tax or VAT depends on where you and your client are and whether you’re registered. Show it as a separate line, and confirm the rules with an accountant — this guide is about invoicing mechanics, not tax advice.
Sending it — and getting paid
Email the invoice as a PDF attachment with a subject like Invoice #0014 — $2,400, due Aug 23. Include a payment link. Then follow up on a schedule instead of a mood: polite nudge at +7 days, firmer note at +14, phone call after that. Invoices with a payment link and automated reminders mostly pay themselves.
Want to price the job before you invoice it? Use the free invoice calculator. Prefer working from a file? Grab a free Word invoice template. And if you’d rather never fill a template again, see how to automate invoices.