Marginal vs Effective Tax Rate in Canada: The Difference Explained

Two rates, two jobs

People use the phrase "my tax rate" as if there is one number, but there are two, and they answer different questions.

Your marginal rate is the tax you pay on your next dollar of income. It is the rate that applies to the top slice of what you earn, and it is the number that matters when you are deciding whether to take on extra work, contribute to an RRSP, or realize a capital gain.

Your effective rate is the total tax you pay divided by your total income. It is the average across every dollar you earned, and it is always lower than your marginal rate. It is the number that tells you what tax actually cost you over the year.

Mixing the two up is the single most common tax misunderstanding, and it leads people to turn down raises and skip deductions for no good reason.

How brackets actually work

Canadian income tax is progressive, which means income is taxed in layers. Each bracket has its own rate, and that rate only applies to the income that falls inside that bracket, not to your whole income.

So if a bracket boundary sits at, say, $57,000 and you earn one dollar above it, only that one dollar is taxed at the higher rate. Everything below the boundary is still taxed at the lower rates it always was. You never lose money by crossing into a higher bracket, because the higher rate never reaches back down to the income beneath it.

This layering is exactly why your average tax rate ends up well below the rate on your top dollar.

The effective rate is always lower

Take someone earning $90,000 in Ontario. Their top dollars are taxed at the combined federal and provincial bracket rate that applies at that income, which is their marginal rate. But the dollars lower down were taxed at the lower brackets, and the first chunk of income was sheltered entirely by the basic personal amount.

The result is an effective rate of 26.1% on income tax, deductions included as computed by the engine, which is noticeably lower than the rate on the final dollar. The gap between the two rates is the whole point of a progressive system.

Effective rate by income

The table below shows total deductions and the effective rate at five income levels in Ontario, computed by the same engine the take-home pay calculator uses. The effective rate rises gradually as income climbs, but it stays below the top bracket rate at every level.

Notice how the effective rate climbs slowly. Doubling income from $40,000 to $90,000 does not double the share lost to deductions, because the lower brackets and the personal amount keep doing their work no matter how high your income goes.

Why the marginal rate is the one for decisions

Any time you are weighing a change at the edge of your income, the marginal rate is the right tool.

• Extra income. A side contract, overtime, or a bonus is taxed at your marginal rate, because it sits on top of everything else. Knowing that rate tells you what you actually keep — see how bonuses are taxed for the common withholding confusion.
• RRSP contributions. A deduction saves you tax at your marginal rate, since it comes off your top dollars first. That is why a contribution is worth more to a higher earner. The RRSP Tax Refund Calculator applies your marginal rate to estimate the refund.
• Capital gains. A realized gain is added on top of your other income, so the tax on it is set by your marginal rate at that point.

The effective rate is the wrong number for all of these, because none of them are spread evenly across your income. They land on the top.

The raise myth

The belief that a raise can leave you worse off, because it "pushes you into a higher bracket," is simply false under a progressive system.

Only the income above the bracket boundary is taxed at the higher rate. The raise is always a net gain. You might keep a smaller share of the dollars above the boundary than the dollars below it, but you still keep a positive amount of every extra dollar. There is no income level in Canada where earning one more dollar leaves you with less money after tax.

The confusion is understandable, because the marginal rate on those top dollars can feel high. But high is not the same as more than 100 percent, and that is what it would take for a raise to actually cost you.

Frequently asked questions

What is the difference between marginal and effective tax rate? The marginal rate is the tax on your next dollar of income. The effective rate is your total tax divided by your total income. The effective rate is always lower because lower brackets and the basic personal amount reduce the average.

Which rate should I use for an RRSP decision? The marginal rate. A deduction reduces your highest-taxed dollars first, so the saving is calculated at your marginal rate, not your average.

Can a raise actually leave me with less money? No. Only the income above a bracket boundary is taxed at the higher rate, so a raise always increases your after-tax income.

Why is my effective rate so much lower than my bracket? Because most of your income was taxed in lower brackets, and the basic personal amount shelters the first portion entirely. Only your top dollars reach your marginal bracket.

How do I see my own effective rate? Enter your income and province into the Take-Home Pay Calculator. It reports your combined effective rate alongside the dollar breakdown.