Updated Checked by the Tax-Services.ca editorial team How we check
The Ontario surtax is an extra 20% charged on your Ontario tax once that tax passes $5,818 in 2026, and another 36% on the part above $7,446. It isn’t a separate rate on your income. It’s a top-up on a number you’ve already worked out, and most people never reach it. If your pay is under about $95,000, you’ll owe none.
Who pays the Ontario surtax?
Only people whose basic Ontario tax is above $5,818. That’s tax after the basic personal amount and other credits, not income. With just the basic amount claimed, the line is crossed at roughly $94,900 of taxable income. Someone with a lot of credits, say a big medical claim or donations, crosses it later.
Below that, nothing. If you earn $60,000 in Ontario, you can stop reading about the surtax and go and do something more fun.
What do the two steps look like?
| Basic Ontario tax | Surtax added |
|---|---|
| $5,818 or less | None |
| $5,818.01 to $7,446 | 20% of the amount over $5,818 |
| Over $7,446 | 20% over $5,818, plus 36% over $7,446 |
The thresholds come from the CRA’s 2026 payroll tables for Ontario. Read the second row as a fee on the slice of tax, not on the slice of income. That’s the bit people trip on.
How much does the surtax cost at different incomes?
We ran taxable incomes through the engine behind our income tax calculator. The figures below claim only the basic personal amount, so your own numbers will differ once other credits come in.
| Taxable income | Basic Ontario tax | Surtax |
|---|---|---|
| $80,000 | $4,454.52 | $0 |
| $100,000 | $6,284.52 | $93.30 |
| $120,000 | $8,360.05 | $837.47 |
| $150,000 | $11,708.05 | $2,712.35 |
| $200,000 | $17,788.05 | $6,117.15 |
At $150,000 the surtax alone is more than a typical monthly mortgage payment. That’s why the top Ontario rates look so much bigger than the 11.16% or 12.16% printed in the bracket table.
What does the arithmetic look like for one person?
Take Maya in Ottawa, with $120,000 of taxable income and only the basic amount claimed. Her basic Ontario tax is $8,360.05. That’s over both thresholds, so the sum has two parts. Twenty per cent of the $2,542.05 above $5,818 is $508.41. Thirty-six per cent of the $914.05 above $7,446 is $329.06. Together that’s $837.47, which matches the table, and it brings her Ontario tax to $9,197.52. Federal tax comes on top of that.
Why are the last dollars taxed so heavily?
Once you’re above $7,446 of basic tax, each extra provincial dollar carries the surtax in full. The rate is multiplied by 1.56, which is 1 plus 20% plus 36%. So the 11.16% bracket, which starts at $107,785 of taxable income, works out to about 17.4% in practice, and the 13.16% bracket to about 20.5%. You add the federal tax on top. The CRA’s 2026 rates page lists the Ontario brackets those percentages come from.
Want to see it on your own numbers? The marginal tax rate calculator prints the rate on your next dollar. One warning from our testing: near $200,000 it can show a jump that also reflects the Ontario Health Premium, which rises in narrow bands of income there. The surtax isn’t the whole story.
Do deductions help if you’re in the surtax zone?
Yes, a bit more than usual. A deduction lowers taxable income, so it lowers basic Ontario tax, and the surtax shrinks with it. At the 12.16% bracket, $1,000 off taxable income cuts basic Ontario tax by $121.60. Multiply by 1.56 and the real provincial saving is about $190, before federal tax. That’s a ballpark, but it shows why an RRSP deduction is worth more to someone well above $100,000.
Mistakes and limits
The most common slip is applying the surtax to income. It’s applied to tax, and it comes after credits, so a donation credit can pull you back under a threshold, and a smaller tax bill means a smaller surtax. The tax refund calculator is a quick way to test that.
Two more limits. The surtax is separate from the Ontario Health Premium, which is its own charge, and Ontario’s own credit for low-income workers isn’t in our surtax figures. And the thresholds move with indexation, so what’s true for 2026 won’t be true forever. We haven’t found the 2027 amounts yet.
Other provinces? The CRA’s 2026 rate page shows no surtax for Prince Edward Island, which is one way Ontario stands out.
Where we got these figures
The brackets and rates are from the Canada Revenue Agency‘s page on 2026 tax rates and income brackets. The surtax thresholds of $5,818 and $7,446 are in the CRA’s 2026 payroll deductions tables for Ontario (T4032-ON). Worked examples come from our own calculator engine and use 2026 figures. This site isn’t linked to the CRA or the Government of Ontario.
Frequently asked questions
What is the Ontario surtax in 2026?
It's 20% of your basic Ontario tax above $5,818, plus 36% of the part above $7,446.
At what income does it start?
With only the basic personal amount claimed, at about $94,900 of taxable income. Other credits push that higher.
Is the surtax the same as the Ontario Health Premium?
No. The health premium is a separate charge based on taxable income. The surtax is calculated on your Ontario tax.
Can credits reduce the surtax?
Yes. Ontario credits come off basic tax first, so a lower basic tax means a lower surtax.
Do other provinces have one?
The CRA's 2026 rate page shows no surtax for Prince Edward Island. Ontario is the one with a surtax on that page.
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- Ontario income tax and sales tax in 2026
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