How to write an invoice

What an invoice has to do

An invoice does two jobs. It tells the customer exactly what they owe and why, and it tells them how and when to pay. If either part is unclear, the invoice sits in a pile.

It is also your record. Your bookkeeper, your accountant and your customer’s accounts team will all look at it later, so write it for a stranger who wasn’t on the job.

What to include

• Your business name, address, phone and email.
• Your customer’s name and billing address or email.
• A unique invoice number, such as 1042 or 2026-042.
• The invoice date, and when the work was done.
• A due date written as a date, not only “Net 30”.
• One line per item: description, quantity, price and line total.
• Sales tax as its own line, if you charge it.
• Any deposit or payment already received, taken off.
• The total due, clearly marked.
• How to pay: a payment link, bank details, or who to make a check out to.
• Your license or tax ID, if your state or customer requires it.

Write it step by step

1. Start from your last invoice number and add one. Never reuse a number.
2. Fill in both sets of contact details. A wrong email is the most common reason an invoice goes unseen.
3. List the work in plain words. “Replace kitchen faucet, 2 hours” beats “Labor”.
4. Show parts and materials separately from labor, with quantities, so the total adds up in the customer’s head.
5. Add tax if it applies, then subtract any deposit.
6. Set the due date and put the payment method right under the total.
7. Read it once as the customer. Would you know what to do next?

A filled-in sample

You can build this one in your browser with the free invoice generator and save it as a PDF.

Mistakes that slow payment

• No due date, so the customer treats it as “whenever”.
• A vague total with no line items, which invites questions.
• Sending it days later, after the customer has moved on.
• No easy way to pay. Make them hunt for your address and they will wait.
• Changing the price from the estimate without saying why. Compare against the estimate first.

Details worth adding for different jobs

Keep a copy of every invoice you send, along with the estimate it came from. If a customer asks about a charge in six months, you want the answer in one place.

• Hourly work: show the hours and the rate, so the labor line can be checked.
• Materials: list each part or give a materials total with receipts available. Say if you add a markup.
• Travel or call-out fees: give them their own line, so they don’t look like padding.
• Repeat customers: keep one number series and put the job address or reference on every invoice.
• Work for a business: include their purchase order or job number if they gave you one.

Send it the same day

The best time to invoice is while the job is fresh and the customer is happy. Email it or text a link before you leave the street. More on that in how to get paid faster.

Paylark is opening soon: it builds the invoice from your phone, sends it by email or text, and lets the customer pay by card, Apple Pay or bank transfer.