What to Include on an Invoice: Checklist

A professional invoice is not long. It is complete. The same dozen or so elements appear on almost every good invoice, and leaving one out is the usual reason an invoice is queried, delayed or rejected. This guide lists every element, explains why it is there, shows an example for each and tells you which ones your country may require by law.

If you want to build one straight away, the free invoice generator already has a field for each element in this checklist, so you can work through the list as you type. For the full process from blank page to sent PDF, read how to make an invoice.

Quick answer: Every invoice should show who is billing whom, a unique invoice number, the issue date, what is being charged for (with quantities and prices), any tax, the total due, and how and when to pay. If you are registered for VAT, GST or sales tax, add your tax number and the tax breakdown.

Who this checklist is for

The checklist works for anyone who sells to another person or business: freelancers, contractors, shops, agencies, consultants and tradespeople. If you are just starting, treat it as a template for what a complete invoice looks like. If you have been invoicing for years, use it as an audit: lay your last invoice next to it and see what is missing. Most people find one or two gaps, such as a PO number, a due date or a clear currency, and fixing those is often enough to speed up payment.

It is also useful from the other side. If you receive invoices, the same list tells you what to expect, and what to ask a supplier to add if it is missing.

The essentials at a glance

Here is the short version. The sections below explain each item in turn.

#	Element	Required?	One-line reason
1	Title (“Invoice” or “Tax invoice”)	Yes	Says what the document is
2	Your business name and contact details	Yes	Identifies the seller
3	Your tax or registration number	If registered	Often a legal requirement
4	Client name and address	Yes	Identifies the buyer
5	Unique invoice number	Yes	Lets both sides refer to it; needed for records
6	Issue date	Yes	Starts the payment clock
7	Due date and payment terms	Yes	Tells the client when to pay
8	Supply date or period	Often	Fixes the tax period and what was covered
9	PO number or reference	If given	Helps the client match it
10	Line items: description, quantity, unit price, amount	Yes	Shows what is charged
11	Subtotal, discount, tax, shipping	As applicable	Lets the client check the total
12	Total and currency	Yes	The amount due
13	Payments received and balance due	If applicable	Prevents double payment
14	Payment methods and instructions	Yes	Makes it easy to pay
15	Late fee or interest wording	If agreed	Only if agreed beforehand
16	Notes	Optional	A thank you, project name or reference

Required, recommended and situational

It helps to group the elements by how much they matter, because the rules differ.

Group	What belongs in it	Why
Always	Title, seller, buyer, invoice number, date, description, amounts, total	Without these it is not a usable invoice
Required when registered for tax	Tax number, tax rate and amount, supply date, sometimes buyer’s tax number	The tax authority needs it
Strongly recommended	Due date, payment terms, payment instructions, PO number	Gets you paid on time
Situational	Shipping address, delivery date, contract number, project code, licence number	Depends on the job or the client
Nice to have	Logo, thank-you note, payment link, QR code	Professional polish

If you remember only the first three groups, you will produce a correct invoice almost every time.

1. The title: “Invoice” or “Tax invoice”

Put the word Invoice at the top in a clear heading. It sounds obvious, but a document that is not labelled can be mistaken for a quote or a statement and ignored.

In countries with a goods and services tax, the title is sometimes dictated. In Australia the document is usually headed “Tax invoice” when GST is charged, and the ATO requires the words “tax invoice” to appear. In the UK you may see “VAT invoice”. If you are unregistered, plain “Invoice” is correct.

2. Your business name and contact details

Show who is sending the invoice:

• Your legal name or registered trading name.
• Your postal address.
• An email address and, where useful, a phone number.
• A website if it helps the client confirm who you are.

If you trade under a name different from your legal name, show both, with the trading name more prominent. Accounts departments pay legal entities, so the legal name has to be visible somewhere.

3. Your tax or registration number

If you are registered for VAT, GST, HST or a similar tax, your registration number normally has to appear on invoices that charge that tax. Examples of what it is called: VAT number (UK and EU), GST/HST number or Business Number (Canada), ABN (Australia), EIN or sales tax permit number (United States, depending on the case).

If you are not registered, you do not need one, and you must not show a number that is not yours. Sole traders in some places may also show a company registration or business licence number; show it if your rules require it.

4. The client’s name and address

Show who is being billed:

• The customer’s exact legal or trading name.
• The billing address.
• A contact name if you know who processes invoices.
• Their tax number, where required (for example for B2B invoices within the EU).

Copy these from the contract, quote or purchase order rather than from memory. A misspelled name is a common reason for a large company to return an invoice. If goods are delivered elsewhere, add a separate Ship to address.

5. The invoice number

Every invoice needs a unique number. It lets both sides refer to it (“invoice 1042”), helps you notice a missing document and, in many countries, is a legal requirement. In the UK, for example, a full VAT invoice must show a sequential number that uniquely identifies it.

Good numbering follows two rules: never reuse a number, and keep the sequence running without unexplained gaps. A number can be a plain count (1, 2, 3) or include the year or a client code (2026-001, ACME-014). See invoice number formats for the patterns and how to choose.

6. The issue date, supply date and due date

Dates do more than decorate the page. There are up to three:

• Issue date: the day you create the invoice. It starts the clock for payment terms.
• Supply date (or tax point): the day goods were delivered or the work was completed, or the period covered, for example “September 2026”. Tax systems often care about this date.
• Due date: the last day to pay without being late.

Write dates in an unambiguous format. “03/04/2026” means 4 March in some countries and 3 April in others, so “3 April 2026” or “2026-04-03” is safer when you work across borders.

7. Payment terms

Payment terms state when and under what conditions the invoice should be paid. Examples are “Due on receipt”, “Net 14”, “Net 30” and “50% on acceptance, balance on completion”. Always show the terms and the actual due date so nobody has to count.

Shorter terms are paid faster, and terms you have agreed in the quote or contract should match what is on the invoice. For more on choosing and wording terms, see invoice payment terms.

8. A PO number or reference

If the client gave you a purchase order number, a project code or a contract reference, put it on the invoice. Large organisations match invoices to orders automatically, and an invoice without the reference may sit unprocessed. It costs nothing to include and it is the single most common fix for “why has my invoice not been paid?”.

9. Line items: description, quantity, unit price and amount

Each line should have four things: what it is, how many, the price per unit and the total for the line. The description is the part that does the most work:

Instead of	Write
Design	Logo design: 3 concepts and 2 revision rounds
Labour	Electrical repairs, 3 hours at $70/hour, 8 Oct
Materials	Cable, 20 m at $2.50/m, and 2 sockets at $8 each
Consulting	Strategy workshop, 4 hours, 8 Oct, with written summary

One thing per line, and use the same units as the quote. Expenses you pass on should be separate lines. For a deeper look at descriptions with examples, see how to make an invoice.

10. Subtotal, discount, tax and shipping

After the lines comes a short calculation. Show each step on its own row so the client can verify the arithmetic:

1. Subtotal (sum of lines).
2. Discount, as a percentage or an amount, if you agreed one.
3. Tax (the rate and the amount) calculated on the discounted price.
4. Shipping or delivery, if charged.
5. Total.

If you charge tax, show the rate and the amount separately, and say whether your prices include it. Mixed rates (for example some zero-rated items) should be shown by rate. The sales tax on invoices guide explains the common cases.

11. The total, currency and balance due

The total is the number the client will look for first, so make it unmissable. Always state the currency if there is any chance of confusion ($ can mean US, Canadian or Australian dollars). If a deposit or earlier payment has been received, show it and then the balance due, so the client pays the right amount.

12. Payment methods and instructions

Make paying as easy as possible:

• Bank name, account name and number, routing, sort code or IBAN.
• A payment link for cards or online wallets.
• The accepted methods and any you do not take.
• The reference to quote, usually the invoice number.

A client who has to email you to ask where to send the money has just added days to the payment. For international clients, include the full details their bank needs, and say who pays transfer fees.

13. Late payment terms

If you charge late fees or interest, say so on the invoice, using wording the client has already agreed. For example: “A late fee of 1.5% per month applies to balances unpaid after the due date.” Do not add a fee that was not in your agreement; in some places there are statutory interest rules and in others limits on what you can charge. See invoice late fees.

14. Notes and extras

Use a short notes area for things that help the client but are not part of the calculation:

• A thank-you line.
• The project or job name.
• A reminder of the next milestone or invoice.
• A warranty or return period for goods.
• A link to your terms and conditions.

Keep it brief. Long legal text belongs in the contract, not on the invoice.

What the rules require in different countries

This is a summary of the main requirements in four common markets. It is general information, not tax or legal advice, and the rules are updated, so check the official source for your case.

Country	What it expects on a standard business invoice
United Kingdom	For a full VAT invoice: a sequential number that uniquely identifies it, the supply date and issue date, your name, address and VAT number, the customer’s name and address, a description with quantity, the VAT rate and amounts per rate, and the total. A less detailed invoice is allowed for supplies of £250 or less including VAT.
European Union	A sequential number, issue and supply dates, supplier and customer VAT details, a description, the taxable amount per rate, the rate and the VAT amount, as set out in the EU VAT rules and applied by each member state.
Canada	For GST/HST, the CRA’s requirements increase with the invoice amount: under $30 the supplier name, date and total; from $30 also the supplier’s registration number and the tax shown; from $150 also the customer’s name, the payment terms and a description of the supply.
Australia	A tax invoice is needed for sales above $82.50 including GST. It must show the words “tax invoice”, your identity and ABN, the date, a description, the price and the GST, with more detail required for sales of $1,000 or more, including the buyer’s identity.
United States	No single federal format. Sales tax is handled by states, and many require tax to be shown separately. Keep a clear record that supports your income and your customers’ deductions.

Our guides on UK VAT invoices, GST invoices in Canada and Australia and sales tax go deeper.

Simplified and modified invoices

Some systems allow a lighter invoice for small amounts. The UK’s less detailed VAT invoice (for sales of £250 or less including VAT) needs fewer items, and Canada’s lowest tier needs only name, date and amount. These are options, not requirements; a fuller invoice is always acceptable. If you are unsure, include more rather than less.

Other special cases include:

• Pro forma invoices, which are preliminary and should say so. See pro forma vs commercial invoice.
• Credit notes, which reduce an earlier invoice and must refer to it. See what a credit note is.
• Self-billed invoices, where the buyer issues the invoice on the seller’s behalf under an agreement; each system has specific marking rules.
• Reverse-charge invoices, where the buyer accounts for the tax. The invoice usually carries a statement to that effect.

Industry-specific extras

Some jobs call for extra details:

Industry	Common extras
Construction and trades	Site address, job or contract number, licence number, stage or milestone, labour and materials shown separately
Consulting and freelance	Project name, hours or day rate, deliverables, expenses with dates
Retail and e-commerce	Order number, product names or SKUs, shipping address, return policy
Legal and professional services	Matter or file number, fee earner, disbursements listed separately
Healthcare	Patient or service reference, procedure codes where required, insurer details
Transport and logistics	Consignment or tracking number, origin and destination, weights

When a client or an industry body specifies a format, follow it. Ask for their invoicing instructions at the start of the job.

What happens when an element is missing

It is easier to remember what to include when you know what goes wrong without it. Each row below is a real, common delay.

If this is missing	What usually happens
Invoice number	The accounts team cannot log it; it is returned or ignored
Client’s legal name	Large companies reject it because it does not match their supplier record
PO number	The invoice cannot be matched to an order and waits in a queue
Due date or terms	The client applies their own terms, often 30 to 60 days
Description	The client asks “what is this for?” and holds payment until answered
Tax number (when registered)	The buyer cannot reclaim tax and asks for a corrected invoice
Currency	The client pays the wrong amount or asks which currency you mean
Payment details	The client emails to ask, and payment waits for the reply
Contact details	Nobody can ask a question, so the invoice stalls

Almost all of these are fixed in seconds before you send, and take days to fix after.

Describing work that is hard to describe

Some jobs do not break neatly into units. The same rule applies: say what, how much and when, in terms the client would recognise.

Creative work. Name the deliverables and the number of revisions: “Brand identity: logo (3 concepts, 2 revisions), colour palette, one-page usage sheet.” Avoid “Design services”.

Retainers. State the period and what it covers: “Monthly marketing retainer, October 2026: up to 10 hours of content planning and 4 posts.”

Hourly work. Show hours and rate: “Website development, 12.5 hours at $60.00 per hour, 6 to 10 October.” If the detail is long, attach a timesheet and refer to it.

Bundled prices. If you agreed a fixed price for a package, show the package as a single line and list what it includes underneath. A client who later asks about the cost of one part will find it was never separately priced, which is correct.

Expenses. Show what, when and the amount, and say whether they are charged at cost: “Train ticket, London to Bristol, 8 October, at cost.”

Product bundles. Use the product names the client sees on your site or order, and the SKU if you have one, so their records match.

How the elements change for different situations

The same checklist applies to every invoice, but some situations add or alter an element.

Situation	What changes
Deposit invoice	Title it clearly (“Deposit invoice”), describe what it is a deposit for, and show the balance expected
Final invoice after a deposit	Show the earlier payment as a line or in the paid-to-date row
Recurring invoice	State the period covered and keep numbers sequential
Foreign currency	State the currency, exchange-rate basis if relevant, and who pays bank fees
Discount	Show the percentage or amount and apply it before tax
Partial delivery	List what was delivered now and say what is still to come
Credit note	Refer to the original invoice number and give the reason
Reverse-charge supply	Add the statement required by your tax authority

If your job has special requirements, put them in the quote or contract first so the invoice just repeats them.

Layout and readability

An invoice is a form people scan. A few layout choices make it easier to approve:

• Put the most important facts at the top right: the invoice number, date and due date. Put the total due in a clearly separated, larger block near the bottom right.
• Keep it on one page when you can. A long invoice should repeat the invoice number on every page.
• Use plain fonts and enough white space. Decorative fonts and background images hurt legibility and printing.
• Align numbers to the right and keep the same number of decimal places, so amounts line up.
• Use one accent colour at most. A coloured header band is fine; a rainbow is not.
• Name the file well. Include the client and the number, for example AwasiUmar_invoice_1042.pdf.
• Check it on a phone. Many people open invoices on a phone, so a clean one-column document is better than a complicated layout.

The invoice generator uses a simple portrait layout with a colour strip and also offers a wider landscape layout for invoices with many columns.

An invoice with each element marked

Here is a complete invoice with the numbers from the checklist in brackets.

INVOICE (1) No. 1042 (5) Date: 14 October 2026 (6) Due: 13 November 2026, Net 30 (7)

From (2): Harris Design, 123 Example Street, Springfield, IL 62701, haris@example.com Tax ID (3): 12-3456789

Bill to (4): Awasi Umar Ltd, 456 Sample Avenue, Austin, TX 73301 PO number (8): 8841

Description (9)	Qty	Rate	Amount
Brand identity: logo, palette, usage sheet	1	$900.00	$900.00
Website design: home plus 4 pages	1	$1,400.00	$1,400.00
Subtotal (10)			$2,300.00
Sales tax 8% (10)			$184.00
Total (11)			$2,484.00 USD
Deposit received 2 Oct (11)			-$1,000.00
Balance due (11)			$1,484.00

Payment (12): bank transfer to Harris Design, account 0000 0000, reference “Invoice 1042”. Late payment (13): 1.5% per month on overdue balances. Notes (14): Thank you for your business.

You can recreate this invoice, field for field, in the invoice generator.

What not to put on an invoice

Some information does not belong and can cause harm:

• Full card numbers or security codes. Never ask for or print them.
• Personal data you do not need, such as a client’s date of birth.
• Internal notes or cost margins. Keep your cost calculations off the client’s copy.
• Vague promises, such as “work to be completed soon”, that are not part of the agreement.
• Anything you cannot support, such as a tax number that is not yours.
• Large images that make the PDF heavy and slow to open.

Showing tax clearly on the invoice

Tax is where invoices most often go wrong, so it deserves its own section. The aim is that a reader can see the tax-free amount, the rate, the tax and the total without doing any sums.

Layout	Example	When to use
One rate, tax added	Subtotal $1,000.00, Sales tax 8% $80.00, Total $1,080.00	Most B2B invoices
One rate, prices include tax	Total $1,080.00 including sales tax 8% of $80.00	Consumer sales and some trades
Several rates	Standard-rated 20% $500.00 net, VAT $100.00; reduced 5% $200.00 net, VAT $10.00	VAT systems with multiple rates
Exempt or zero-rated lines	Exempt supplies $300.00, no tax	Items outside the tax
Reverse charge	Net $2,000.00, VAT 0.00, “Reverse charge: customer to account for VAT”	Certain cross-border or domestic supplies

Tips that keep the tax section clean:

• Say whether prices include tax. One sentence removes the doubt: “All prices exclude tax unless stated.”
• Calculate tax on the discounted price, not the original.
• Round at the line or invoice level consistently, following your authority’s rules, so totals add up.
• Name the tax. Write “Sales tax”, “VAT” or “GST”, not just “Tax”, where more than one could apply.
• Do not charge tax you are not registered to charge. If you are not registered, show no tax.

The invoice generator supports one tax line with a percentage or a fixed amount and a “prices include tax” option. If you need several rates on one invoice, issue separate invoices or check how your accounting system and your authority expect it to be shown.

Electronic invoices and structured data

Most small businesses send a PDF, which contains all of the elements above as readable text. Larger buyers and some governments ask for structured electronic invoices, where the same elements are supplied as machine-readable fields so their systems can read them without keying. The elements are the same; only the format changes. If a client asks for one, they will give you the specification, and an invoicing system or a service can convert your data. For everyday use, a clear, well-labelled PDF with a unique number is fine.

Wording questions people ask

Should I write “Invoice” or “Tax invoice”? Use “Tax invoice” only if your tax authority requires that wording or you are registered and charging tax in a system that uses it. Otherwise, “Invoice” is correct.

Should I say “Please pay” or “Payment due”? Either. Be polite and specific: “Payment due by 13 November 2026 by bank transfer.”

Can I add a discount for early payment? Yes, if you offer it. State it clearly: “2% discount if paid within 10 days.” The guide to payment terms explains the common 2/10 net 30 pattern.

Should I put my terms and conditions on the invoice? A short line referring to them is enough: “Subject to our terms and conditions at example.com/terms.” Long terms belong in the contract.

Do I need a signature? Usually not. A typed business name is enough; add a signature only where a contract or a client requires it.

What language should the invoice be in? The language the client uses with you, or the language required where you both operate. The invoice generator can switch its labels into 16 languages if you need a document in another language.

A printable checklist

Run through this before you send:

Check	Done
“Invoice” (or “Tax invoice”) clearly titled
My name, address, contact and tax number (if registered)
Client’s legal name and address; PO number if given
Unique invoice number, in sequence
Issue date, supply date or period, due date
Clear description, quantity, unit price and amount for each line
Subtotal, discount, tax rate and amount, shipping
Total with currency; deposits and balance due
Payment terms and how to pay
Late fee wording, only if agreed
Notes, thank-you
Saved as a PDF with a clear file name

Common mistakes when filling in an invoice

Mistake	Consequence	Fix
Missing invoice number or duplicate numbers	Rejected or hard to track	One unbroken sequence
No due date	Client pays whenever	Show terms and the date
Vague descriptions	Disputes and delay	Specific lines with dates and quantities
Missing tax number when required	Client cannot reclaim tax; can be a compliance issue	Add it if registered
Wrong client name	Returned by their accounts	Copy from the contract
Tax calculated before discount	Wrong total	Discount first, then tax
No payment details	Client has to ask	Add bank details or a link
Currency not stated	Confusion about amounts	State it next to the total
Editing a sent invoice	Mismatched records	Issue a credit note and a new invoice

How a generator helps you remember

A tool does not replace knowing the rules, but it stops you forgetting. In the invoice generator the fields run in the same order as this checklist: your details and logo, client and PO number, number and dates, line items, discount, tax and shipping, amount paid, terms and notes. The totals are calculated in the order described above, and the file is named after your client and the invoice number. Tick the checklist as you type and you will rarely send an incomplete invoice.

Line descriptions by profession

If you are unsure how specific to be, these examples show the level of detail that works.

Profession	Example line descriptions
Web developer	“Contact form with email notifications and spam filter, 6 hours at $75”
Photographer	“Wedding photography, 8 hours, 12 September, 400 edited images delivered by link”
Plumber	“Replace kitchen mixer tap, 1.5 hours labour at $70, tap supplied at $64”
Bookkeeper	“Monthly bookkeeping, September 2026, up to 80 transactions”
Copywriter	“Website copy, 5 pages at 400 words, with one round of edits”
Cleaner	“End-of-tenancy clean, 2-bedroom flat, 14 October, 5 hours with 2 staff”
Trainer	“Personal training sessions, 4 sessions of 60 minutes in October”
Wholesaler	“Printer paper A4, 80gsm, 20 boxes of 5 reams at $24.00 per box”

Notice that each line says what, how much and, where it matters, when. None of them needs more than one line.

Your first invoice versus your hundredth

A first invoice is mostly about completeness: you are checking that every element is there and that you understand it. A hundredth invoice is mostly about consistency: you want the same fields in the same places, the same numbering and the same wording, so clients learn where to look.

Some practical differences:

• On your first invoice, take your time with the tax and legal details, because you are setting a pattern. Ask your accountant if you are registered for tax.
• By your tenth, you should have standard wording for terms, a standard description style and a fixed payment block.
• By your hundredth, you will probably want a saved template, automatic numbering and a register, so the only things you type are the client and the lines.

Whatever stage you are at, the checklist does not change. What changes is how quickly you can fill it in, which is why a tool that lays the fields out for you, such as the invoice generator, is worth using early.

A final read-through before you send

A last check takes a minute and catches most errors. Read the invoice in this order:

1. The top: is the number correct and is the date today’s?
2. The parties: does the client’s name match the contract exactly? Is your tax number there if required?
3. The money: add the lines yourself, apply the discount, then tax, then compare with the total.
4. The terms: is the due date a real date, and are the payment details complete?
5. The extras: does the PO number appear? Is the currency clear?
6. The file: is it a PDF, named with the client and number?

If you can say “yes” to all six, the invoice is as likely as it can be to be paid without a question.

Next steps

You now have a complete list of what belongs on an invoice and why. The next steps are to create one, read how to make an invoice for the full workflow, and choose a numbering scheme from invoice number formats. If you are unsure which document you need at all, read invoice vs receipt vs bill.