GST/HST Filing for Small Businesses in Canada: What You Need to Know
If you run a small business in Canada, GST/HST is something you can't afford to get wrong. Miss a filing deadline, overclaim input tax credits, or use the wrong calculation method — and you're looking at CRA penalties, interest charges, and potentially an audit.
This guide breaks down everything Canadian small business owners need to know about GST/HST: when to register, how to file, which method to use, and how to avoid the most common mistakes.
Do You Need to Register for GST/HST?
You must register for GST/HST when your business revenue exceeds $30,000 in a single calendar quarter or over four consecutive quarters. This threshold applies to most businesses — with some exceptions for certain exempt supplies like residential rent and healthcare services.
You can also register voluntarily before hitting the $30,000 threshold — which can be beneficial if you have significant business expenses and want to claim input tax credits (ITCs) right away.
⚠️ Important: Once you exceed the $30,000 threshold, you must register within 29 days. Failing to register on time means you're still liable for all GST/HST you should have collected — even if you didn't charge it to customers.
GST vs. HST: What's the Difference?
The rate you charge depends on the province where your customer is located:
| Province/Territory | Tax Type | Rate |
|---|---|---|
| Ontario | HST | 13% |
| British Columbia | GST + PST | 5% + 7% |
| Alberta | GST only | 5% |
| Quebec | GST + QST | 5% + 9.975% |
| Nova Scotia / NB / NL / PEI | HST | 15% |
| Manitoba | GST + RST | 5% + 7% |
| Saskatchewan | GST + PST | 5% + 6% |
If you serve customers across multiple provinces, you need to apply the correct rate based on the place of supply rules — not just your home province.
When Are GST/HST Returns Due?
Your filing frequency depends on your annual taxable revenue:
| Annual Revenue | Filing Frequency | Due Date |
|---|---|---|
| $1,500,000 or less | Annual | 3 months after fiscal year-end |
| $1,500,001 – $6,000,000 | Quarterly | One month after each quarter |
| Over $6,000,000 | Monthly | One month after reporting period |
Most small businesses file annually or quarterly. The CRA will assign your filing frequency when you register, but you can request a change if your revenue changes significantly.
What Are Input Tax Credits (ITCs)?
Input tax credits allow you to recover the GST/HST you paid on business expenses. This is one of the most valuable aspects of being registered — it reduces the net amount you owe to the CRA.
Common eligible expenses for ITCs include:
- Office rent and utilities
- Business equipment and supplies
- Professional services (accounting, legal)
- Software subscriptions used for business
- Business vehicle expenses
To claim an ITC, you must have a valid receipt or invoice showing the GST/HST paid. Keep every receipt — the CRA can ask for documentation up to four years back.
Which Calculation Method Should You Use?
Regular Method: You track all GST/HST collected from customers and subtract all ITCs from business expenses. The difference is what you remit to the CRA. This method works best for businesses with significant expenses.
Quick Method: A simplified option for businesses with annual revenue under $400,000. Instead of tracking every ITC, you remit a flat percentage of your gross sales.
💡 The Quick Method can save money, but it's not always better. If your business expenses are high, the Regular Method usually results in a lower net remittance. A bookkeeper can run the numbers both ways to find your best option.
5 Common GST/HST Mistakes to Avoid
- Not charging GST/HST on taxable supplies: When in doubt, assume your supply is taxable unless you can confirm otherwise.
- Missing filing deadlines: The CRA charges late-filing penalties and daily compound interest.
- Claiming ITCs without valid receipts: A bank statement is not enough — you need an invoice showing the GST/HST amount.
- Mixing personal and business expenses: Only business expenses qualify for ITCs.
- Forgetting to file a nil return: Even with zero sales, you must file a return to avoid penalties.
How to File Your GST/HST Return
You can file your return in three ways:
- Online: Through My Business Account on the CRA website (fastest/recommended).
- Integration: Through your accounting software.
- By mail: Using the GST34 paper form (slowest).
Once filed, payment can be made through your bank's portal or the CRA's My Payment service.
Frequently Asked Questions
What happens if I collect GST/HST but don't remit it?
The CRA treats this as a serious offence leading to penalties, interest, and potential personal liability.
Can I claim ITCs on meals and entertainment?
Yes, but only 50% of the GST/HST paid is eligible as an ITC.
What is a GST/HST audit?
A review of your filed returns, invoices, and records, often triggered by large ITC claims or inconsistent history.
How far back can the CRA reassess my GST/HST returns?
Generally four years from the filing date, but there is no time limit if fraud is suspected.
Does MaxRefund Business handle GST/HST filings?
Yes. We manage registrations, filings, and CRA correspondence for small businesses.
Book a Free Consultation →MaxRefund Business provides online bookkeeping, payroll, and tax services for small businesses across Canada. All content is for informational purposes only and does not constitute legal or tax advice.
