AMT Calculator

AMT mainly affects taxpayers who report large capital gains, exercise employee stock options, claim the lifetime capital gains exemption (LCGE), donate appreciated securities, or carry large interest/carrying charges. The AMT recalculates your tax on a broader income base and applies a flat 20.5% rate; if that result exceeds your regular federal tax, you pay the higher amount. Most people with ordinary salary income never trigger it because of the exemption — the bottom of the 4th federal tax bracket (about $181,440 for 2026, $177,882 for 2025).

Starting 1 January 2024 the federal AMT rate rose from 15% to 20.5%, and the basic exemption jumped from $40,000 to the bottom of the fourth federal tax bracket — about $173,205 for 2024 (indexed annually). AMT only applies to adjusted taxable income above that exemption, which is why it targets higher-income years rather than typical wage earners.

For regular tax, only 50% of a capital gain is taxable. Under the 2024+ AMT, capital gains are included at 100% — so the normally tax-free half is added back to the AMT base. This is the single most common AMT trigger: a large one-off gain (selling a business, rental property, or concentrated stock) can push adjusted income well above the exemption even when regular tax looks modest.

Yes. Under the 2024+ rules only 80% of the Charitable Donation Tax Credit is allowed for AMT (down from 100%), and 30% of capital gains on donated publicly-listed securities are now included in the AMT base (previously 0%). Large donors who gift appreciated shares are among those most likely to see AMT for the first time.

AMT is usually a timing issue, not a permanent cost. Any AMT you pay creates a carry-forward credit you can apply against regular federal tax for the next 7 years, to the extent your regular tax exceeds AMT in those years. If you have a one-off high-income year followed by normal years, you often recover the AMT. If high preference income recurs every year, some AMT can become permanent.

The federal AMT applies across Canada, and most provinces levy their own provincial AMT as a percentage of the federal AMT. Quebec runs its own minimum tax system through Revenu Québec rather than mirroring the federal calculation. This calculator estimates the federal AMT only — confirm provincial minimum tax with a tax professional or your provincial return.