What is the minimum information an invoice must include?

At minimum: who is billing whom (business and customer names), a unique invoice number, an issue date, what was supplied (line items with quantity and price) and the total amount due. Everything else — tax, discounts, payment terms, notes — is added on top of that core.

Do I need a logo on my invoice?

No. A logo is optional. It makes an invoice look more established and easier to recognise at a glance, but an invoice without one is just as valid as long as the core fields are complete.

What is the difference between an invoice number and a PO/reference number?

The invoice number is yours — a unique, sequential identifier you assign for your own records. A PO (purchase order) or reference number belongs to the customer, referencing their internal approval or order. Including their reference on your invoice helps their accounts team match it to the right payment without following up.

Do payment terms need to be an exact date?

Either works. Some invoices state a specific due date; others state terms like 'Net 30' (due 30 days after the invoice date) and leave the customer to calculate it. Stating both a clear due date and the terms that produced it avoids any ambiguity.

Billing & Invoicing

What to include on an invoice

5 min read

A complete invoice does two jobs at once: it tells your customer exactly how much to pay, by when and for what, and it gives you a clean record for your own bookkeeping. Missing a field usually means a delayed payment while your customer emails back to ask for it.

The fields below apply whether you are a freelancer billing a single client or a business invoicing customers in another country — nothing here is specific to one market.

The core fields every invoice needs

The fields a complete, payable invoice always has.
Field	Why it matters
Business information	Your name, address and contact details — who the customer is paying.
Customer information	Who is being billed, so the invoice reaches the right accounts team.
Invoice number	A unique, sequential ID for your records and your customer's.
Issue date	When the invoice was raised — the reference point for any payment terms.
Line items	What was supplied: a description, quantity and unit price per item.
Total due	The final amount payable, after any discount and tax.

Fields you only need sometimes

Common, but not always required — add them when they apply to you.
Field	When it applies
Due date / payment terms	Whenever you expect payment by a specific point, e.g. Net 30.
Tax (VAT, GST, sales tax…)	Whenever you are required or choose to charge tax on the sale.
Discount	Whenever you are reducing the price for this customer or order.
Business or customer tax ID	VAT number, ABN, EIN, GSTIN or similar — often required for B2B or cross-border billing.
PO / reference number	When your customer issued a purchase order or reference to quote.
Notes / terms & conditions	Payment instructions, late fees, or anything else worth stating.
Logo	Optional — makes the invoice look more established, but not required.

A simple flow for creating one

Add your business details and the customer you are billing.
Give the invoice a number, an issue date and, if relevant, a due date or payment terms.
Add one line item per product or service, with quantity and unit price.
Apply a discount or tax if either applies to this sale.
Check the total, then send or download the invoice.

The international invoice generator covers every field above — including an optional logo and a choice of three templates — for 35 currencies and any tax name (VAT, GST, sales tax or your own). If you specifically need Indian GST fields such as CGST/SGST/IGST and HSN/SAC codes, use the GST invoice generator instead.

What to include on an invoice

The core fields every invoice needs

Fields you only need sometimes

A simple flow for creating one

Do the maths automatically

Free Invoice Generator

Invoice Generator

Frequently asked questions

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