Calgary Small Business Taxes: GST-Only Sales, the Alberta AT1, and Getting Caught Up
Calgary businesses charge only 5% GST, but Alberta corporations may also file an AT1 return with Alberta TRA. Rates, deadlines and how to catch up missed years.
Calgary businesses charge 5% GST with no provincial sales tax, pay 11% combined tax on a CCPC's first $500,000 of active business income (9% federal + 2% Alberta), and, unlike Ontario or BC companies, many Alberta corporations also file a separate Alberta corporate return (AT1) with Alberta Tax and Revenue Administration. Missing the AT1 is one of the most common gaps we see in Alberta catch-up files.
Alberta in one table
| Item | Rule |
|---|---|
| Sales tax | 5% GST only (canada.ca) |
| Small business rate | 2% Alberta + 9% federal |
| General rate | 8% Alberta + 15% federal = 23% |
| Provincial return | AT1 filed with Alberta TRA, generally due 6 months after year-end (alberta.ca) |
| Payroll tax | No provincial payroll health tax, but WCB Alberta premiums apply |
| Registry | Alberta annual return through a registry agent |
The two-return problem
A Calgary corporation that's behind is often behind twice: on the federal T2 with the CRA and on the AT1 with Alberta. They're separate agencies with separate penalties and separate letters. Some corporations are exempt from filing the AT1. Whether yours is depends on its taxable income and Alberta's current exemption criteria, so check the year in question.
Who we hear from in Calgary
Mostly owner-managed businesses between about $200k and $4M in revenue: consultants who incorporated in a busy year, online and service businesses, and clinics that added locations. The pattern is the same. Growth took the owner's time, the bookkeeping stopped in 2022 or 2023, and the accountant has stopped returning calls (here's what to do about that).
Example (hypothetical)
A Calgary IT consulting corporation earning about $600k hasn't filed since its 2022 year-end. The catch-up plan: rebuild three years of books, file three GST returns (it's an annual filer), three T2s and, where required, three AT1s. Then the owner's own T1s, because dividends or salary also have to be reported. If neither the CRA nor Alberta has made contact, a VDP application covers the federal side, and Alberta has its own voluntary disclosure process.
Calgary-specific costs that aren't tax
The City of Calgary requires business licences for many business types, and the Alberta tourism levy applies to short-term accommodation. Neither is a CRA filing, but both show up in the books.
Getting help
Sansar works with Calgary businesses through our Calgary accounting and Calgary bookkeeping services for one all-inclusive flat rate, with the 100% Happiness Guarantee. Start with catch-up bookkeeping or late tax filing.
Book a call for a custom quote → · How onboarding works and what documents we need →
FAQ
Is there PST in Calgary? No. Alberta has no provincial sales tax, so most sales carry only 5% GST.
Do Alberta corporations file a separate provincial tax return? Many do. Alberta administers its own corporate income tax, and corporations that don't meet an exemption file the AT1 with Alberta TRA, separately from the federal T2.
What's the small business tax rate in Calgary? 11% combined (9% federal + 2% Alberta) on a CCPC's first $500,000 of active business income.
Can I catch up both T2 and AT1 returns together? Yes. Once the books are done, both returns come from the same numbers and are filed for each missing year.
Does Alberta have a voluntary disclosure program? Alberta TRA has its own voluntary disclosure process, separate from the CRA's VDP. Confirm the current terms with Alberta before applying.
Written by Gurdeep Sangha, founder of Sansar Solutions, a Vancouver-based bookkeeping and tax firm serving small businesses across Canada (mainly Ontario, Alberta and BC). Sansar is not a CPA firm; Notice to Reader and review engagements go through partner CPAs. This guide is general information, not tax or legal advice for your situation. Last reviewed: October 2026.