An Alberta business was charging a provincial sales tax that does not exist in the province. We corrected the billing and refunded customers.
Alberta has no provincial sales tax, so only the federal GST applies on taxable supplies. This client had configured its billing system from an Ontario template and was adding a provincial component to Alberta invoices. We corrected the tax configuration, quantified the over-collection, refunded the affected customers, and adjusted the GST returns for the periods involved so remittances matched what was actually collectible.
E-commerce sits across provincial sales tax regimes, marketplace collection rules and inventory held in other jurisdictions.
Registration is mandatory once taxable supplies pass $30,000 over four consecutive calendar quarters. Input tax credits require documentation that scales with invoice size.
Why it bites: Unmatched input tax credits are the first thing disallowed in a sales-tax review, and the assessment covers every period reviewed.
The CRA requires business records to be kept for six years from the end of the tax year they relate to, in a form that allows the return to be verified.
Why it bites: Where records cannot support the return, the CRA is entitled to assess on its own estimate — and the burden of disproving that estimate falls on the taxpayer.
Every engagement above was priced as a fixed fee agreed before the work started, and paid only once the client had reviewed the result. If any of this looks like your situation, the first step is a free 15-minute call — we will tell you plainly whether there is anything worth doing.
Reviewed for the 2025 tax year by Udit Gupta, Founder and Tax Accountant. This case study is based on a real client engagement handled by Tax Filings Canada; the client's name and identifying details have been changed. Outcomes depend on your own facts.
