GST/HST for the self-employed: compliant quotes and invoices

1. The $30,000 threshold: when do you have to register?

As long as your taxable sales stay under $30,000 over four consecutive calendar quarters, you are a "small supplier": GST/HST registration is optional. As soon as you cross that threshold, registration becomes mandatory (with the CRA — or Revenu Québec if you're in Québec, where it administers both GST and QST).

Even below the threshold, registering voluntarily often pays off: once registered, you recover the GST/HST paid on your business expenses (tools, materials, gas, phone) through input tax credits (ITCs).

2. The calculation: it depends on your province

Every tax is calculated on the pre-tax amount. What changes is which taxes apply:

• GST only (5%) — Alberta, Yukon, NWT, Nunavut
• HST — Ontario 13%, Nova Scotia 14%, New Brunswick / Newfoundland / PEI 15% (one combined tax)
• GST + QST — Québec: 5% + 9.975%, each on the pre-tax amount (14.975% combined)
• GST + PST/RST — BC 5% + 7%, Saskatchewan 5% + 6%, Manitoba 5% + 7%

Example in Ontario: $1,000 of work + HST 13% = $1,130. Round each tax line to the cent — repeated rounding errors across dozens of invoices always get noticed. Our GST/HST calculator does it for every province, including the reverse calculation.

3. What must appear on your invoices

Once registered, every invoice must show:

• your name or business name (the one attached to your tax numbers);
• the date and an invoice number (sequential, no gaps);
• the description of the goods or services;
• the tax amounts shown separately (or a note that they're included);
• your GST/HST registration number (and QST number in Québec).

On a quote, showing taxes isn't legally required — but it's best practice: the client accepts a final price, not a 15% surprise. Start from our free quote template and free invoice template.

4. The three most common mistakes

• Charging taxes without being registered. Prohibited — and a savvy client will notice (your tax numbers are missing).
• Numbering that skips. INV-2026-004 then INV-2026-007: in an audit, gaps raise questions. Keep one continuous sequence for quotes and invoices.
• Losing track of the $30,000 threshold. It's measured on a rolling 4-quarter basis — not by calendar year. Watch it as soon as contracts pick up.

Automatic tax calculation, without thinking about it

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