What must be on an invoice in the United States

IRS Publication 583 states that the law does not require any specific kind of records. What matters federally is that your records are complete enough to support the income and deductions on your return, not that an invoice carries particular fields. No federal sales tax or VAT; sales and use tax is set by each state. There is no legal requirement for sequential invoice numbering. Keep invoices for 3 years.

Source: IRS, retrieved 2026-08-05.

Mandatory fields

Mandatory invoice fields in the United States (IRS, 2026-08-05)
FieldWhen it applies
No federal requirementAlways IRS Publication 583 states that the law does not require any specific kind of records. What matters federally is that your records are complete enough to support the income and deductions on your return, not that an invoice carries particular fields.

The rules at a glance

Tax, numbering, retention and reverse charge in the United States, with the authority behind each value
RuleIn the United StatesSource
TaxNo federal sales tax or VAT; sales and use tax is set by each stateIRS
Sequential number requiredNoIRS
Keep records for3 yearsIRS
Reverse charge wordingNot verifiedn/a
Simplified invoice thresholdNot verifiedn/a
E-invoicingNot verifiedn/a

"Not verified" means we could not read the value off a primary source, so we do not state one. It is not a claim that no rule exists. See our methodology.

How long to keep invoices

3 years. Three years is the baseline period of limitations, rising to six years where income is understated by more than 25 percent, and with no limit where a return is fraudulent or was never filed.

There is no such thing as a legally required US invoice format

This page exists mostly to correct an assumption. Anyone arriving from Europe expects a list of mandatory invoice particulars, and federally there is not one. IRS Publication 583 puts it directly: the law does not require any specific kind of records. The obligation is that your records substantiate what you put on your return, not that a document carries prescribed fields.

That does not mean nothing applies. Sales and use tax is set state by state, so whether you charge it, at what rate, and what your invoice has to show can all differ across a state line. There is no federal answer to those questions and this page does not offer one: check with the revenue department of the state you are selling into.

The practical effect for a freelancer or small business is freedom with a catch. You can format an invoice however you like, and you still want an unbroken number series, a clear description and a stated payment term, because those are what get you paid and what get you through an audit. They are simply good practice here rather than law.

Making the invoice

Once you know what your invoice needs, the invoice generator builds it in your browser. It has a tax field, a discount field, VAT number fields for both parties and a notes field for wording such as a reverse-charge statement. Nothing you type is uploaded.

This page describes published requirements. It is not advice on your own situation, and whether a rule applies to you depends on facts we do not have. For that, go to IRS directly or talk to an accountant.

Other jurisdictions

European UnionNetherlandsGermanyFranceBelgiumUnited KingdomIrelandAustraliaCanada

Sources

Every value on this page was read off one of these pages on the date shown. Where a value could not be confirmed, the table above says "Not verified" rather than showing a number.

Frequently asked questions

What must be on an invoice in the United States?

no federal requirement. The full list is in the table on this page, taken from IRS.

Do invoice numbers have to be sequential in the United States?

No. There is no federal requirement for sequential invoice numbering. An unbroken series is still standard practice and makes your own records defensible. Source: IRS.

How long do I have to keep invoices in the United States?

3 years. Three years is the baseline period of limitations, rising to six years where income is understated by more than 25 percent, and with no limit where a return is fraudulent or was never filed. Source: IRS.