How to Add HST to an Invoice in Canada (Step-by-Step Guide)

Knowing how to add HST to an invoice in Canada isn't optional once you cross the $30,000 CAD mark in taxable sales. Cross that threshold — even across a handful of strong months — and CRA expects you to register, collect, and remit. Miss it, and they'll bill you for the tax you should have charged anyway. Here's the exact process: rates by province, the four-step calculation, what CRA legally requires on your invoice, and how to remit without a cash-flow crisis.

TL;DR

Register for GST/HST once you hit $30,000 CAD in taxable revenue over four consecutive calendar quarters.
HST applies in Ontario (13%), Nova Scotia (15%), New Brunswick (15%), PEI (15%), and Newfoundland & Labrador (15%). Other provinces use GST-only (5%) or a separate provincial tax.
Your invoice must show your 9-digit Business Number + RT0001, the HST rate, and the HST dollar amount.
Remit to CRA as net tax: HST collected minus Input Tax Credits (ITCs) on your expenses.
Most exports to US clients are zero-rated — no HST required.

When You Actually Have to Charge HST

The trigger: $30,000 CAD in taxable supplies within any single calendar quarter, or cumulatively across four consecutive quarters. Hit that number and you have 29 days to register. CRA doesn't wait, and neither should you.

Building an invoice in Invoicito's generator, with a live sample-invoice preview (demo data shown).

Once registered, every taxable invoice to a Canadian client carries HST. The rate you charge depends on where your client receives the supply — not where you operate. That distinction catches contractors off guard constantly. A client in Halifax pays 15% regardless of whether you're billing from Winnipeg.

Province	Rate	Tax Type
Ontario	13%	HST
Nova Scotia	15%	HST
New Brunswick	15%	HST
PEI	15%	HST
Newfoundland & Labrador	15%	HST
BC, Alberta, Saskatchewan, Manitoba	5%	GST only
Quebec	5% GST + 9.975% QST	Separate taxes

Two carve-outs that matter: zero-rated supplies — most services exported to US clients, certain basic foods — require no HST. Exempt supplies — most financial services, residential rent — aren't taxable at all. Billing mostly American companies? You're almost certainly zero-rated. Don't charge HST on those invoices.

$30K

The Registration Trigger

Exceed $30,000 CAD in taxable supplies over four consecutive calendar quarters and GST/HST registration becomes mandatory — not optional. You have 29 days from the day you cross the line.

How to Calculate and Show HST on Your Invoice

Four steps. That's it.

1
List your subtotal — the price of services or goods before any tax.
2
Multiply by the applicable rate — Ontario clients: subtotal × 0.13. Nova Scotia, NB, PEI, NL: × 0.15. Western Canada: × 0.05 (GST only).
3
Add HST as a separate line item below the subtotal. CRA requires it shown explicitly — not buried in a total.
4
Show the total as subtotal + HST. Clean, compliant, done.

Worked Example

Priya, a Toronto-based UX consultant, invoices a client $1,500 for a website audit.

Consulting fee: $1,500.00
HST (Ontario 13%): $195.00
Total due: $1,695.00
GST/HST Registration #: 123456789 RT0001

That registration number isn't optional. CRA explicitly requires it on every invoice once you're registered. It's the single most forgotten field — and without it, your invoice is technically non-compliant.

Tight overhead shot of a crisp Canadian business invoice laid flat on a pale oak desk, fountain pen resting across it, t — Tight overhead shot of a crisp Canadian business invoice laid flat on a pale oak desk, fountain pen

Here's the full CRA checklist for a compliant invoice:

Your full legal name or business name
Your GST/HST registration number (9-digit BN + RT0001)
Date of supply
Description of the service or goods
Subtotal before tax
HST rate applied (e.g., "13% HST")
HST dollar amount
Total amount due

💡 Did You Know?

Invoices under $30 carry simplified CRA requirements. For $30–$149.99, you need your BN but can skip the per-item rate breakdown. Over $150, full disclosure is required. When in doubt, use the complete format regardless of amount — it costs nothing and protects you from audit exposure.

How to Remit HST to the CRA — Without Getting Stung

Collecting HST is only half the obligation. You have to send it to CRA on time or the penalties compound fast.

Your reporting period is tied to revenue. Under $1.5M: annual filing. $1.5M–$6M: quarterly. Over $6M: monthly. Most freelancers start annual, but CRA can reassign you to quarterly if volumes climb.

"Net tax = HST you collected minus Input Tax Credits on eligible business expenses. You're not remitting every dollar of HST you charged — only the net."

File via CRA's My Business Account or paper form GST34. Due dates: annual filers get three months after fiscal year-end. Quarterly filers get one month after each quarter-end. Missing either triggers interest and penalties immediately.

⚠️ Don't Touch the HST You Collect

It was never yours. Plenty of contractors have burned through collected HST as operating income, then faced a remittance bill they couldn't cover. Open a dedicated account. Every dollar of HST that hits your bank goes straight there — untouched — until filing day.

A focused Canadian small business owner — mid-40s, reading glasses, natural salt-and-pepper hair — seated at a bright op — A focused Canadian small business owner — mid-40s, reading glasses, natural salt-and-pepper hair — s

The Bottom Line

Once registered, every taxable Canadian invoice needs your BN, the applicable rate, and the HST dollar amount shown separately. Calculate it as subtotal × rate, remit the net to CRA by your filing deadline, and keep collected tax ringfenced from operating funds. Get those three habits right and you won't have a problem.

Frequently Asked Questions

Do I charge HST if my client is in another province with a different rate?

Yes — and you charge their province's rate, not yours. Place-of-supply rules point to where the client receives the service. A Nova Scotia client pays 15% even if you're billing from Ontario. Check your client's location on every invoice. Never default to your home province rate.

What happens if I forgot to add HST to an invoice I already sent?

Issue a correcting invoice or addendum showing the HST owed. If you were registered at the time of supply, you were required to collect it. That means you may absorb the cost or request the additional amount from your client — but either way, CRA is owed the tax on that supply regardless of whether you collected it.

Can I claim HST back on my business expenses?

Yes. That's what Input Tax Credits (ITCs) are for. Paid HST on software subscriptions, office supplies, subcontractors, or equipment? Deduct that amount from the HST you owe CRA at filing. Keep every receipt. CRA can audit ITCs, and unsupported claims get clawed back — with interest.

Stop calculating HST manually on every invoice.

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Bottom Line

HST registration isn't optional once you cross $30,000 in revenue — and getting it wrong costs more than getting it right ever could.

Register within 29 days of crossing the threshold
Apply place-of-supply rules on every invoice — your client's province, not yours
File quarterly if you're under $6M and want to stay organized
Claim every ITC you're entitled to — it's money back in your pocket
Keep HST collected in a separate account so filing day is never a cash-flow crisis

How to Add HST to an Invoice in Canada: A Step-by-Step Guide