What a Canadian invoice must show: the CRA rules by amount.

Checked against official sources on 9 September 2026. This is general information for Canadian small businesses, not tax advice; your accountant knows your situation.

Why the CRA cares what is on your invoice

Your invoice is your customer's evidence. A GST/HST registrant who buys from you claims the tax back as an input tax credit, and the CRA can deny that claim if the invoice or receipt is missing required information. The rules are set out in the Input Tax Credit Information Regulations and scale with the size of the sale. The dollar bands were raised on 20 April 2021; the old $30 and $150 figures still circulate on the web and in an unrevised CRA memorandum, but the current bands are $100 and $500.

Sales under $100

• Your business name, or the name you trade under
• The date of the invoice, or the date the tax was paid if there is no invoice
• The total amount paid or payable

Sales of $100 to $499.99: everything above, plus

• Your GST/HST registration number
• The amount of GST/HST charged, or a statement that the price includes it together with the rate that applied
• If the sale mixes taxable, exempt and zero-rated items, which items were taxed at which rate

Sales of $500 and over: everything above, plus

• The customer's name, trading name, or the name of their agent
• The terms of payment
• A description of each item or service sufficient to identify it

Do invoice numbers have to be sequential?

The CRA's published documentation requirements do not list an invoice number among the mandatory elements at any band, and we could not find an official page that requires numbers to be sequential. What the law does require is books and records that let the CRA determine what you owe and what you can claim. In practice that means every invoice should have a unique, traceable identifier, and an unbroken sequence is the easiest way to prove nothing is missing. Hakkuu numbers invoices sequentially for you; treat any claim that the CRA mandates a particular numbering scheme as unconfirmed.

Payment terms and reminders

Terms are required on sales of $500 and over, and they are the thing most small businesses leave vague on every invoice. "Due on receipt" or "Net 30" printed on the invoice is what makes a reminder fair rather than awkward. A reasonable cadence is a reminder on the due date and again a week or two later, sent during business hours. In Hakkuu you set that cadence once and reminders send themselves.

Keep a copy

You must keep your copy of every invoice, along with the receipts behind your own purchases, for six years from the end of the tax year they relate to. Electronic copies are fine as long as they stay readable. The receipts guide covers what that means in practice.

How Hakkuu handles this

Every Hakkuu invoice carries your business name, the date, a sequential number, the customer's name, a description of each line, the terms, the tax as its own line with the rate, and your registration number. Which is to say, it satisfies the $500-and-over band on every invoice, so you never have to remember the bands.