One of the most common and costly mistakes Alberta small business owners make is not knowing when they are required to register for the Goods and Services Tax. The consequences of missing the registration threshold are real: the CRA can require you to remit GST you never collected from your clients, out of your own pocket, plus penalties and interest.
This guide explains exactly when you must register, why voluntary registration often makes sense even before you hit the threshold, and what input tax credits mean for your business.
Alberta and GST — What Makes This Province Different
Alberta is the only province in Canada with no provincial sales tax. Businesses in Alberta collect and remit the federal Goods and Services Tax at a rate of 5%. There is no Harmonized Sales Tax (HST) in Alberta. This is a meaningful advantage for Alberta businesses and consumers compared to provinces where HST reaches 13% or 15%.
The $30,000 Small Supplier Threshold
Under the Excise Tax Act, a business is considered a small supplier — and is not required to register for GST — as long as its worldwide taxable supplies remain below $30,000. The CRA uses a rolling four-consecutive-calendar-quarter test: if your taxable revenue exceeds $30,000 in any single calendar quarter, or over any four consecutive calendar quarters, you are no longer a small supplier and must register.
Once you exceed $30,000, you are required to register within 29 days. From the date you exceed the threshold, you must begin charging GST on all taxable sales — even before your registration is complete. If you fail to register and charge GST, the CRA can assess you for the GST you should have collected, regardless of whether you collected it from your clients. That assessment comes out of your pocket.
What Counts Toward the Threshold
The threshold applies to worldwide taxable supplies — the revenue from taxable goods and services, not your total income. It includes zero-rated supplies (like certain exports and medical devices, which are taxable at 0%) but does not include exempt supplies (such as residential rent, most health care services, and educational services). If your business generates exempt supplies, those revenues do not count toward the $30,000 threshold.
Understanding what qualifies as taxable versus exempt in your specific industry matters. Misclassifying your revenues can lead to either failing to register when required, or registering unnecessarily. Your CPA can confirm how the rules apply to your business.
Mandatory Registration Regardless of Revenue
Certain businesses must register for GST regardless of their revenue level. This includes taxi and rideshare drivers (Uber, Lyft) regardless of income, and non-residents who make taxable supplies in Canada in certain circumstances. If your business falls into a specially regulated category, the standard small supplier threshold may not apply.
Why Voluntary Registration Often Makes Sense
Even if your revenue is below $30,000, there are meaningful reasons to register voluntarily. The most important: Input Tax Credits (ITCs). When you are a GST registrant, you can claim back the GST you paid on eligible business expenses — equipment, professional services, supplies, rent. If your business has significant expenses, those ITCs can represent real money.
Consider a St. Albert consultant billing $25,000 annually who spent $15,000 on business expenses including computer equipment, software, and office costs. Without GST registration, that 5% GST paid on expenses — roughly $750 — is simply a business cost. As a registrant, it is recovered.
Voluntary registration also signals professionalism. Many business-to-business clients expect GST registration and may question why you are not registered if your invoice does not include a GST number. It can also be advantageous to register before you expect to cross the threshold so that you have systems in place rather than scrambling to register at the last moment.
GST Filing Periods
Once registered, the CRA assigns you a reporting period based on your annual taxable supplies. Businesses with taxable sales under $1.5 million file annually. Those between $1.5 million and $6 million file quarterly. Those above $6 million file monthly. You can request more frequent filing if that suits your cash flow.
Filing deadlines vary by reporting period. Annual filers generally have three months after their fiscal year-end to file and pay. Quarterly and monthly filers have one month after the end of each reporting period. Missing filing deadlines triggers late-filing penalties and daily compound interest on amounts owing.
Input Tax Credits — Tracking What You Can Claim
An ITC allows you to recover the GST paid on eligible business expenses. To claim ITCs, you must keep proper documentation: for purchases over $30, you need the supplier’s name, the GST registration number, the date, and the amount of tax paid or payable. CRA audits of GST returns frequently focus on ITC documentation. If you cannot produce proper invoices to support your ITC claims, the CRA can disallow them and assess the difference plus interest.
This is one of the areas where clean, organized bookkeeping pays direct financial dividends. Businesses with well-maintained records claim every ITC they are entitled to. Businesses with poor records routinely leave money on the table.
As of November 2025 — Online Registration Only
As of November 3, 2025, the CRA no longer accepts GST/HST registrations by phone. All new registrations must be completed online through the CRA’s Business Registration Online (BRO) platform. If you need to register, ensure you complete the process online.
What to Do Now
If you are approaching $30,000 in annual revenue, or if you have significant business expenses and have been hesitant to register voluntarily, a brief consultation with a CPA will clarify your obligations and options. At Nguyen Scott LLP, we assist Edmonton, St. Albert, Leduc, and Drayton Valley businesses with GST registration, ongoing compliance, and maximizing ITC claims.
Book your free 30-minute consultation at nsllp.ca/contact-us/
Nguyen Scott LLP — Chartered Professional Accountants. This article is for general informational purposes only and does not constitute tax or legal advice. Please consult a qualified CPA for advice specific to your situation.