What Must a US Invoice Include?

Required Fields for a US Invoice

The United States does not have a single federal law prescribing an exact invoice format, but standard business practice and tax compliance require the following fields.

1. Your business name and address — or your full name if you are a sole proprietor
2. Your client's name and address — the person or business being billed
3. Unique invoice number — sequential numbering is strongly recommended
4. Invoice date — when the invoice was issued
5. Description of goods or services — detailed enough that the client knows exactly what they are paying for
6. Quantity and unit price — for each line item
7. Subtotal — the total before tax
8. Sales tax (if applicable) — the rate and amount, shown separately
9. Total amount due — the final amount including tax
10. Payment terms — when payment is due (e.g. "Net 30") and accepted methods

Sales Tax on Invoices

Sales tax in the US varies by state, county, and city. Not every transaction is taxable, and rates range from 0% (in states like Oregon and Montana) to over 10% in some jurisdictions.

If you are required to collect sales tax:

• Register for a sales tax permit in each state where you have nexus
• Show the tax rate and amount as a separate line item
• Indicate the jurisdiction — some clients need to know which state or local tax applies

Additional Fields to Consider

Beyond the basics, many US businesses include:

• EIN or SSN — your federal tax identification, especially for B2B transactions
• Purchase order (PO) number — if the client issued one, referencing it speeds up payment
• Late payment terms — e.g. "1.5% interest per month on overdue balances"
• Payment instructions — ACH details, wire transfer info, or a link to online payment

Common Mistakes to Avoid

• Ignoring sales tax obligations — selling into a state where you have nexus without collecting tax can lead to penalties
• Missing payment details — if you do not include your bank or payment details, the client cannot pay promptly
• Vague descriptions — "Professional services" is not enough; describe the work performed
• Not keeping copies — the IRS can audit up to three years back (six in some cases), and you will need your invoices

Create a US-Compliant Invoice

Our US invoice generator includes all the fields you need and handles sales tax calculations automatically.