How to Calculate GST/HST on an Invoice in Canada (Formula, Examples and Requirements)
Step-by-step: calculate GST/HST on an invoice
- Decide the place of supply. Find the province where your customer receives the goods or services. Use the rate table.
- Separate taxable, zero-rated and exempt lines. Only taxable and zero-rated items are on the GST/HST calculation (zero-rated at 0%).
- Add the taxable subtotal.
- Multiply by the rate. Round to the nearest cent.
- Add PST or QST if the province charges it separately (BC, Manitoba, Saskatchewan, Quebec).
- Show each tax on its own line with your GST/HST registration number.
Worked examples
| Item | Amount |
|---|---|
| Example A: Ontario consulting invoice (13% HST) | |
| Consulting, 10 hours × $90 | $900.00 |
| HST 13% | $117.00 |
| Total | $1,017.00 |
| Example B: Alberta goods invoice (5% GST) | |
| Goods subtotal | $1,240.00 |
| GST 5% | $62.00 |
| Total | $1,302.00 |
| Example C: Quebec invoice (GST + QST) | |
| Services subtotal | $1,000.00 |
| GST 5% | $50.00 |
| QST 9.975% | $99.75 |
| Total | $1,149.75 |
| Example D: BC invoice (GST + PST) | |
| Goods subtotal | $500.00 |
| GST 5% | $25.00 |
| PST 7% | $35.00 |
| Total | $560.00 |
Since 2013 QST is calculated on the price before GST, not on a GST-included amount, so the two taxes do not compound.
Calculating tax when the total already includes tax
Divide by (1 + rate). A $565 total in Ontario is 565 ÷ 1.13 = $500.00 before tax, so HST = $65.00. Do not subtract 13% from the total. See the calculator to check your numbers.
What must appear on an invoice for GST/HST?
Customers who claim input tax credits (ITCs) need enough detail on your invoice. The CRA sets tiers by invoice total:
| Invoice total | Minimum information |
|---|---|
| Under $30 | Supplier name or trade name, date, and amount paid |
| $30 to $149.99 | Adds the GST/HST registration number and the total tax (or that tax is included) |
| $150 or more | Adds the customer's name, terms of payment and a description of the goods or services |
For professional invoices it is easiest to always include your business name, BN with the RT0001 account, invoice date and number, customer name, a description, the taxable subtotal, and each tax line.
Common invoicing mistakes
- Charging the seller's province rate instead of the customer's.
- Rounding the tax total instead of each line (be consistent).
- Forgetting to list the GST/HST number.
- Charging GST/HST while not registered (only registrants can collect it).
When you collect the tax, you report it on your return. See GST/HST return due dates.
Frequently asked questions
How do I calculate GST on an invoice?
Multiply the taxable subtotal by the rate for the customer's province and show the tax on its own line. Total = subtotal × (1 + rate).
How do I calculate GST from a total?
Divide the total by 1 plus the rate. For a $105 total in Alberta, 105 ÷ 1.05 = $100 before GST.
How do I calculate GST and QST together?
Charge 5% GST and 9.975% QST, each on the pre-tax price. On $1,000 that is $50 GST and $99.75 QST.
Can I charge GST if I am not registered?
No. Only registered businesses can charge and collect GST/HST.
What must an invoice show for a customer to claim ITCs?
It depends on the total. Invoices of $150 or more need the supplier name, GST/HST number, total tax, customer name, terms and description.