Many incorporated business owners build up investments inside their corporation — and then get a nasty surprise when their low small business tax rate quietly disappears. The culprit is the passive investment income grind: earn too much investment income inside your CCPC and you lose access to the $500,000 small business deduction. Here's exactly how the $50,000 rule works in 2026 and how to plan around it.
Since 2019, a Canadian-controlled private corporation's $500,000 small business limit is reduced by $5 for every $1 of passive investment income above $50,000. The reduction is based on the prior year's passive income, and the small business deduction is fully eliminated once passive income hits $150,000.
| Passive investment income (prior year) | Small business limit remaining |
|---|---|
| $50,000 or less | $500,000 (full) |
| $75,000 | $375,000 |
| $100,000 | $250,000 |
| $125,000 | $125,000 |
| $150,000 or more | $0 (fully ground out) |
Lose the small business deduction and your active income jumps from roughly 11% to 23% tax in Alberta — a steep price for holding investments in the wrong place.
The grind uses a measure called AAII. It generally includes:
It generally excludes income incidental to an active business and capital gains on property used in an active business. Note that associated corporations combine their AAII when applying the $50,000 threshold — so a holding company's investment income can grind the operating company's limit.
Your operating company earns $500,000 of active income. Last year your corporate investment portfolio threw off $100,000 of AAII. The grind reduces your limit by ($100,000 − $50,000) × 5 = $250,000, leaving a $250,000 small business limit. The result:
This is exactly the kind of planning our Calgary tax planning and corporate tax teams handle every year.
A CCPC's $500,000 small business deduction is reduced by $5 for every $1 of passive investment income (AAII) above $50,000 in the prior year, and is fully eliminated at $150,000 of passive income. Losing the deduction raises the tax rate on active income from about 11% to about 23% in Alberta.
Adjusted aggregate investment income (AAII) generally includes interest, rents, royalties, taxable capital gains, and portfolio dividends. It excludes income incidental to an active business and gains on active-business property. Associated corporations combine their AAII when applying the $50,000 threshold.
Keep AAII under $50,000 where possible by timing capital gains, use vehicles whose growth isn't AAII (such as corporate-owned permanent life insurance or an Individual Pension Plan), and draw down the corporate investment balance through salary or dividends. Moving investments to an associated holding company does not avoid the grind.
No. If the holding company and operating company are associated, their passive investment income is combined when applying the $50,000 threshold, so the holdco's investment income still grinds the opco's small business limit.
Swift Accounting Ltd. helps Calgary incorporated business owners with exactly this kind of planning. Contact us for a free consultation.
