Tax brackets

Tax brackets are the divisions at which tax rates change in a progressive tax system (or an explicitly regressive tax system, although this is much rarer). Essentially, they are the cutoff values for taxable income — income past a certain point will be taxed at a higher rate.

Imagine that there are three tax brackets: 10%, 20%, and 30%. The 10% rate applies to income from $1 to $10,000; the 20% rate applies to income from $10,001 to $20,000; and the 30% rate applies to all income above $20,000.

Under this system, someone earning $10,000 would be taxed at a rate of 10%, paying a total of $1,000. Someone earning $5,000 would pay $500, and so on.

Meanwhile, someone earning $25,000 would face a more complicated calculation. The rate on the first $10,000 would be 10%; the rate from $10,001 to $20,000 would be 20%; and the rate above that would be 30%. Thus, they would pay $1,000 for the first $10,000 of income (10%); $2,000 for the second $10,000 of income (20%); and $1,500 for the last $5,000 of income (30%); in total, they would pay $4,500, or an 18% average tax rate.

In practice the computation is simplified by using point–slope form or slope–intercept form of the linear equation for the tax on a specific bracket, either as tax on the bottom amount of the bracket plus the tax on the marginal amount within the bracket:

or the tax on the entire amount (at the marginal rate), minus the amount that this overstates tax on the bottom end of the bracket.

See Progressive tax#Computation for details.

Financial years 2010-11, 2011-12

The above rates do not include the Medicare levy of 1.5%.

Financial year 2012-13

The above rates do not include the Medicare levy of 1.5%

Canada's federal government has the following tax brackets for the 2012 tax year (all in Canadian dollars). Note that the "basic personal amount" of $15,527 effectively means that income up to this amount is not subject to tax, although it is included in the calculation of taxable income.

Each province except Québec adds their own tax on top of the federal tax. Québec has a completely separate income tax.

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