What to Include on an Invoice: The Complete Checklist

Knowing what to include on an invoice is the difference between getting paid promptly and chasing down confused clients for weeks. A complete, professional invoice eliminates questions, satisfies tax authorities, and makes it easy for accounts payable departments to process your payment. Miss a required field and you risk delayed payment, rejected invoices, or compliance issues during an audit.

This checklist covers every element a proper invoice should contain — organized by what's legally required, what speeds up payment, and what's optional but recommended.

The Essential Invoice Checklist

What must every invoice include? At minimum: your business name and contact details, the client's name, a unique invoice number, the invoice date, a due date, an itemized list of goods or services, the total amount due, and payment instructions. Tax jurisdictions may require additional fields like tax registration numbers.

1. Your Business Information

Place this prominently at the top of every invoice:

• Business name (legal name or trading name)
• Address (registered business address)
• Email address (for invoice-related correspondence)
• Phone number
• Tax identification number (EIN in the US, VAT number in the UK/EU, ABN in Australia, GST number in Canada/India)
• Logo (optional but adds professionalism)

The IRS requires that business records — including invoices — clearly identify the source. In VAT jurisdictions, HMRC mandates that your VAT registration number appears on every invoice.

2. Client Information

• Client's full business name (legal entity name, not just a contact person)
• Client's billing address
• Client's email address
• Client's tax ID or VAT number (required for B2B transactions in many EU countries)
• Attention line (the specific person or department handling payment, if known)

Getting the client details right matters more than you think. An invoice addressed to the wrong entity or department often gets bounced back, adding days or weeks to your payment timeline.

3. Invoice Identification

• Invoice number — a unique, sequential identifier. Never reuse invoice numbers. See our guide on invoice numbering best practices for structuring a system that scales.
• Invoice date — the date you issue the invoice
• Due date — when payment is expected. Common terms include Net 15, Net 30, and Due on Receipt. Read more about payment terms to choose the right one.
• Purchase order number (if the client provided one — many corporate clients require this for payment processing)
• Project or reference number (ties the invoice to a specific project, contract, or agreement)

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 rate) across line items.

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

5. Financial Summary

Below your line items, include a clear financial breakdown:

• Subtotal — sum of all line items before tax
• Tax amount — with the tax rate specified (e.g., "VAT 20%: $700.00" or "Sales tax 8.5%: $297.50")
• Discounts — if applicable, show the discount amount and reason (e.g., "Early payment discount 2%: −$70.00")
• Shipping or delivery charges — if applicable
• Total amount due — the final number the client needs to pay, prominently displayed

Make the total impossible to miss. Bold it, increase the font size, or place it in a highlighted box. The faster a client can see what they owe, the faster they'll pay.

6. Payment Instructions

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

• Accepted payment methods (bank transfer, credit card, PayPal, check)
• Bank details (account name, bank name, account number, routing/sort code, SWIFT/BIC for international transfers)
• Online payment link (if you use Stripe, PayPal, or another gateway)
• Payment terms (Net 30, Due on Receipt, etc.)
• Late payment policy (e.g., "A late fee of 1.5% per month applies to overdue balances" — use our late fee calculator to determine appropriate rates)
• Currency — especially important for international transactions

7. Additional Notes and Terms

• Scope of work summary (brief reminder of what was delivered)
• Thank you note (a simple "Thank you for your business" goes further than you'd expect)
• Terms and conditions (warranty information, refund policy, ownership transfer terms)
• Legal disclaimers (if required by your industry or jurisdiction)

What's Required by Law (by Region)

Requirements vary by country. Here's what tax authorities specifically mandate:

Common Mistakes That Delay Payment

1. Missing or incorrect PO numbers. Corporate clients often can't process invoices without a matching purchase order. Always ask for the PO number before invoicing.
2. Vague descriptions. "Services rendered" invites questions. Be specific about what was delivered.
3. Wrong client entity. Invoicing "John" instead of "Smith Corp Ltd" can mean your invoice gets rejected by accounts payable.
4. No due date. Without a due date, your invoice goes to the bottom of the pile. Always specify when payment is expected.
5. Missing tax information. Invoices without required tax details get bounced back in VAT/GST jurisdictions, adding weeks to your payment cycle.

Free Invoice Template with Every Field

Rather than building invoices from scratch, use a tool that includes all required fields by default. InvoiceQuickly generates compliant invoices automatically — just describe the work and every required field is populated for you. You can also browse our invoice templates for industry-specific layouts.

If you prefer creating invoices manually, use this structure as your template:

[Your Logo]
[Business Name]
[Address, Email, Phone, Tax ID]

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

Bill To:
[Client name]
[Client address]
[Client email, Tax ID]

| 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, etc.]

Next Steps

Now that you know what to include, the logistics matter too. Read our guide on how to send an invoice by email for templates and best practices that ensure your invoice gets opened, read, and paid.

Create a complete invoice in seconds with InvoiceQuickly →