What to Include on an Invoice: Required Details

An invoice that’s missing a key detail can be rejected by a client’s accounts team, disallowed by a tax authority, or simply left in a pile while someone emails you to ask. This guide lists everything an invoice should include, separates what is legally required in common systems from what is good practice, and finishes with a printable checklist.

If you want a head start, the BillKit invoice generator already has a field for each item below.

The short answer

Almost every invoice in the world should include:

The word “Invoice” (or “Tax Invoice” where that term is used)
A unique, sequential invoice number
The invoice date (and supply date if different)
Your name, address and tax number (if registered)
Your client’s name and address (and tax number where required)
A description of each item: quantity, unit price and line total
Subtotal, tax rate and tax amount, and total due — in a stated currency
Payment due date and payment instructions

Everything else depends on where you are, who you are billing and whether you’re registered for VAT, GST or sales tax.

Required vs. recommended: the full list

Element	Why it matters	Usually required?
“Invoice” / “Tax Invoice” label	Distinguishes it from a quote or receipt	Yes (wording varies)
Invoice number	Unique identification, audit trail	Yes, for VAT/GST invoices
Invoice (issue) date	Starts payment terms, determines tax period	Yes
Supply/delivery date	Determines when tax is due if different from issue date	Often, for VAT invoices
Seller’s legal name and address	Identifies who must be paid and who owes the tax	Yes
Seller’s tax ID (VAT/GST/ABN)	Lets the buyer reclaim input tax	Yes, if registered
Company registration details	Some countries require them on business documents	Depends on country and entity type
Buyer’s name and address	Identifies who owes the money	Yes for full VAT invoices
Buyer’s tax ID	Needed for reverse-charge and some B2B invoices	Sometimes
Description of goods/services	Shows what’s being paid for	Yes
Quantity and unit price	Lets the buyer verify the total	Yes for VAT invoices in the EU and UK
Net amount per tax rate	Correct tax calculation	Yes for VAT invoices
Tax rate and tax amount	Lets the buyer reclaim tax	Yes, if tax is charged
Total amount and currency	What must be paid	Yes
Exemption or reverse-charge wording	Explains why no tax is charged	Yes, when applicable
Due date / payment terms	Sets the deadline for payment	Strongly recommended
Payment methods and bank details	Removes friction	Strongly recommended
PO number / client reference	Many companies can’t approve invoices without one	When the client uses POs
Logo, thank-you note	Professionalism	Optional

Your details (the seller)

Include your legal name — the name of the person or company that is legally providing the service. If you trade under a different name, show both (“Jane Smith, trading as Smith Copywriting”). Add your address, an email that someone actually reads, and your tax number if you have one.

If you are a limited company, check your country’s rules: the UK, for example, requires companies to show their registered name, and business documents commonly carry the company number and registered office address. Many EU countries have similar disclosure rules for business letters and invoices.

Your client’s details (the buyer)

Use the client’s legal entity name, not a brand name or a person’s name, unless you are billing an individual. Large organisations frequently have several legal entities; invoices addressed to the wrong one get bounced back.

Include the buyer’s VAT number when you apply the reverse charge on a cross-border B2B sale in the EU, and wherever local rules require it. Australia’s GST rules, for example, require tax invoices of A$1,000 or more to show the buyer’s identity or ABN.

Dates and numbering

Invoice date — the date you issue it.
Supply date (tax point) — the date goods were delivered or services completed, if different.
Due date — when payment must arrive. See payment terms explained.
Invoice number — unique and sequential. Read invoice numbering for formats that keep auditors happy.

Line items

For each line include a clear description, quantity, unit price (net of tax) and line total. If you apply different tax rates to different items, show the rate per line or group the lines by rate.

Good descriptions are specific: “Copywriting — 5 product pages (approx. 300 words each), incl. 1 revision round” beats “Writing”. If your client has to ask what something is, you have just added days to your payment time.

Totals and tax

Show the calculation transparently:

Line	Example
Subtotal (net)	€2,000.00
Discount (10%)	−€200.00
Taxable amount	€1,800.00
VAT 21%	€378.00
Total due (EUR)	€2,178.00

If you don’t charge tax, say why. Common examples:

Not registered because you’re under the threshold — some countries require a specific statement (Germany’s small-business rule, for instance, is usually referenced as “§ 19 UStG”).
Reverse charge on a B2B cross-border service — note “Reverse charge” and show both VAT numbers. See how to charge VAT on invoices.
Exempt supply — cite the exemption where your local rules require it.
Export outside the tax area — note that it’s zero-rated or not subject to tax, as appropriate.

US sellers should read sales tax on invoices in the US, where the rules are state-based.

Payment information

The fastest-paid invoices tell the client exactly how to pay:

Bank name, account holder name, IBAN/account number and BIC/SWIFT (or routing number in the US)
A payment link if you accept cards or online payments
The reference to use (the invoice number)
Accepted currency — and who covers bank fees for international transfers. If you invoice abroad, see invoicing in a foreign currency.

Terms and notes

Keep footer text short and useful: payment terms, late-payment interest or fees (only if agreed in your contract or permitted by law), required legal statements, and a thank-you. If you work on retainers or recurring billing, state the period covered (“Services for November 2026”).

Simplified invoices

Several tax systems allow a shorter “simplified” invoice for small amounts — typically retail sales. The EU VAT Directive lets member states permit simplified invoices for amounts up to €100 (some set different limits), and the UK allows simplified VAT invoices for supplies up to £250 including VAT. A simplified invoice can omit details such as the buyer’s address, but can’t be used in every situation (for example, intra-EU supplies). When in doubt, issue a full invoice.

Special cases

Proforma invoices aren’t tax invoices; they’re advance quotes in invoice form. See proforma invoice.
Corrections should be handled with a credit note, not by editing the original.
E-invoicing countries (Italy, increasingly Germany, France, Poland and others) require structured electronic formats for some invoices. See what is an e-invoice.
Receipts confirm payment and contain different details — see invoice vs. receipt or make one with the receipt generator.

Printable checklist

For country-specific requirements, browse our invoice templates by country.

This checklist reflects widely used rules and good practice. Requirements differ by country and change over time; it is not legal or tax advice. Check with your tax authority or an accountant for your situation.