What to Include on an Invoice: 12 Fields Every Invoice Needs

Knowing what to include on an invoice is the difference between getting paid promptly and answering questions from a confused client. A complete invoice lets an accounts payable team match it to a purchase and approve it without coming back to you, and it gives you a record you can rely on later.

This checklist covers the 12 fields every invoice should carry, then what the law adds in the UK and EU, and what US federal tax guidance does and does not say. If you want the result on one page, skip to the fill-in invoice layout or start from a free invoice template. For the full country-by-country rules, see the UK invoice requirements and the other country guides linked below.

The 12-field invoice checklist

What must every invoice include? At minimum: your business name and contact details, the client's name and address, a unique invoice number, the invoice date, the date of supply, a description of what you supplied, quantities and prices, the subtotal, any tax, the total due, the due date and payment instructions. VAT-registered sellers must add further details.

The sections below explain each group of fields.

1. Your business information

Place this prominently at the top of every invoice:

• Business name (your legal name, or a trading name with your legal name where your local rules require it)
• Address
• Email address for invoice questions
• Phone number (optional)
• Tax registration number, where you have one and your tax authority requires it on invoices, such as a UK or EU VAT number
• Logo (optional)

In the UK, GOV.UK's guidance on what invoices must include adds rules on names: a sole trader using a business name must also show their own name and an address where legal documents can be delivered, and a limited company must show its full name as it appears on its certificate of incorporation. A VAT number is only required if you are VAT-registered; HMRC's VAT invoice rules are covered below.

2. Client information

• Client's full business name (the legal entity, not just a contact person)
• Client's billing address
• Client's email address
• Client's VAT number, where the law requires it (in the EU, mainly when the customer accounts for the VAT under the reverse charge or receives an intra-EU supply of goods; see the EU section below)
• Attention line (the person or department handling payment, if known)

An invoice addressed to the wrong entity or department can be sent back or sit unapproved, which delays payment.

3. Invoice identification

• Invoice number: a unique identifier you never reuse. UK and EU VAT invoices need a sequential number; US federal tax law sets no numbering rule, but your client's AP system will still match your payment by it. See invoice numbering systems for how to set one up and invoice number best practices for handling gaps and corrections.
• Invoice date: the date you issue the invoice.
• Date of supply: when you delivered the goods or finished the service, if different from the invoice date.
• Due date: when payment is expected. Common terms include Net 15, Net 30 and Due on Receipt. Read more about payment terms to choose one.
• Purchase order number, if the client gave you one. Many corporate clients cannot approve an invoice without it, so ask before you invoice.
• Project or reference number, which ties the invoice to a contract or job.

4. Itemized line items

This is the core of your invoice. Each line should include:

Best practices for line items:

• Be specific. "Consulting services" is vague. "Brand strategy consulting: Q1 2026 market positioning" is clear.
• Break large projects into meaningful phases or deliverables.
• Match descriptions to what was agreed in the contract or scope of work.
• Use consistent units (hours, days, flat fee) across line items.

If you're not sure how to structure your line items, our guide on how to write an invoice walks through examples.

5. Financial summary

Below your line items, show:

• Subtotal: the sum of all line items before tax
• Discount, if any, with the reason (for example "Early payment discount 2%")
• Tax amount, with the rate stated (for example "VAT 20%" or "Sales tax 8.5%")
• Shipping or delivery charges, if any
• Total amount due, displayed prominently, with the currency

Worked example (UK, VAT-registered designer):

The 20% figure is the UK standard rate (GOV.UK: VAT rates). A seller who is not VAT-registered would show a total of £3,950.00 and no VAT line.

6. Payment instructions

This section directly affects how quickly you get paid. Include:

• Accepted payment methods (bank transfer, card, PayPal, check)
• Bank details (account name, bank name, account number, routing number or sort code, and SWIFT/BIC or IBAN for international transfers)
• Online payment link, if you use a payment provider such as Stripe or PayPal
• Payment terms (Net 30, Due on Receipt and so on)
• Late payment policy, if your contract and local law allow one (for example "A late fee of 1.5% per month applies to overdue balances"). Rules differ by state and country: see late fee laws by state, and use the late fee calculator to see what a rate means in money.
• Currency, especially for international clients

7. Additional notes and terms

• Scope of work summary (a brief reminder of what was delivered)
• Thank-you note
• Terms and conditions (warranty, refund policy, ownership transfer)
• Any statement your tax rules require, such as a reverse charge note on an EU cross-border invoice

What does the law require, by region?

Requirements depend on where you are and whether you are registered for VAT or GST. This table summarizes the official sources; follow the links for the full rules. Last reviewed 28 October 2026.

If you are registered for VAT or GST, the difference between a tax invoice and an ordinary one matters; see tax invoice vs regular invoice. This is general information, not legal or tax advice; check with your tax authority or an adviser for your situation.

Common mistakes that delay payment

1. Missing or incorrect PO numbers. Corporate clients often can't approve an invoice without a matching purchase order. Ask for the PO number before invoicing.
2. Vague descriptions. "Services rendered" invites questions. Say what was delivered.
3. Wrong client entity. Invoicing "John" instead of "Smith Corp Ltd" can get your invoice rejected by accounts payable.
4. No due date. Without a due date, the client decides when to pay. Always state the date or the terms.
5. Missing tax details. A VAT-registered customer needs a valid VAT invoice to reclaim the VAT, so a missing VAT number or rate usually means a request for a corrected invoice.

A fill-in invoice layout with every field

You can build invoices from a template or in software. InvoiceQuickly can draft the client, line items, rates and terms from a typed or spoken description into an editable invoice that you review before saving (the Free plan includes 5 invoices and 3 AI drafts). Its PDF shows your business details, the invoice number, issue and due dates, the client's details, line items, subtotal, one discount line, one tax line, the total, any recorded payments and the balance due, and your notes and terms. New invoices print the tax ID saved in your business settings and the tax ID saved on the client, such as a VAT number. Invoices created before you saved a tax ID keep their original details. There is no separate PO or supply-date field, so put the PO number and supply date in the notes if your client or tax rules need them.

If you prefer to build invoices yourself, use this structure:

[Your Logo]
[Business Name]
[Address, Email, Phone, VAT number if registered]

INVOICE
Invoice #: [Number]
Invoice date: [Issue date]
Date of supply: [If different]
Due: [Due date]
PO #: [If applicable]

Bill To:
[Client legal name]
[Client address]
[Client email, VAT number if required]

| Description | Qty | Rate | Amount |
|-------------|-----|------|--------|
| [Item 1]    |  1  | $X   | $X     |
| [Item 2]    |  5  | $Y   | $5Y    |

                        Subtotal: $XX
                        Tax (X%): $XX
                        Total Due: $XX

Payment: [Methods and bank details]
Terms: [Net 30 / Due on Receipt / etc.]
Notes: [Thank you, T&Cs, required tax statements]

Next steps

Once the invoice is complete, delivery matters too. Read our guide on how to send an invoice by email for subject lines and message templates.

Create your first invoice with InvoiceQuickly →