Understanding Federal Tax Tables & Income Tax Brackets

Section 3 of the Internal Revenue Code directs the IRS to publish IRS tax tables annually for individuals. The tables include rates, a range of personal income under each rate as well as an estimated taxable income.

The tables allow taxpayers to estimate their liability without making computations. The tax tables for each year’s 1040 are published in a booklet (2016 income tax tables can be found here). The tables contain very narrow ranges of taxable income so that you can arrive at an amount that is as precise as possible.

The IRS tax tables provide estimates for income under $100,000 and a worksheet for incomes above that. Of course, our software will always automatically calculate a users exact liability so estimating is not required.

The federal tax system is progressive through various brackets. A bracket is a range of incomes separated from other ranges and given a certain percentage tax rate. For ordinary income, there are seven brackets, each tied to a rate (percentage): 10%, 15%, 25%, 28%, 33%, 35%, and 39.6%. Tax rates increase as income increases. A range of income, from a base amount to a ceiling amount, falls within each income tax bracket. The range varies, depending on filing status (single, married filing jointly, married filing separately, or head of household).

For example, a single taxpayer’s rates for tax year 2016 (for tax returns that were due, without extension, on April 17, 2017) are as follows:

The tax rates for each bracket are derived from section 1 of the Internal Revenue Code, but are adjusted for inflation each year. The inflation adjustment is designed to prevent “bracket creep,” in which taxpayers would be pushed into higher brackets because of inflation rather than increases in their income levels.

Marginal and Effective Rates

Not all taxpayer income is subject to the rate in which their income tax bracket falls. For example, if a single filer's income falls between $37,651 and $91,150 (25% bracket), only the amount over $37,650 is taxed at the 25% rate. The first $9,275 this individual earns is taxed at 10%, the next $28,375 is taxed at 15%. Just the income over $37,650 is taxed at 25%.

Only the last dollar of income determines the bracket into which a taxpayer falls. Someone making $40,000 annually pays roughly $5,771 or 14.4% of their income. This is their effective tax rate, where the last rate which they are taxed (25%) is their marginal rate.

Confusion about marginal and effective rates is the reason people are sometimes reluctant to move into a higher income tax bracket. The reluctance is largely misplaced. Suppose a taxpayer is given a raise from $35,000 annually to $40,000. If all of this income were taxed at the marginal rate, then this taxpayers after-tax situation would barely change since they are moving from the 15% bracket into the 25% bracket. Fortunately, for all taxpayers only the income within the new bracket is taxed at the 25% rate.

Capital Gains Rates

The federal taxation of "capital gains" (see more here) is also progressive.

The tax rates on short-term capital gains (gains from the sale of investments or assets held for one year or less) are the same as the rates for ordinary income. Short-term capital gains run through the brackets in the same way that ordinary income does in the examples above.

Generally, long-term capital gains (gains from the sale of investments held for more than one year) fall into three brackets, but these three brackets are tied to the seven brackets for ordinary income (and short-term capital gain).

States may also impose their own capital gains rates.