Every year, the IRS lets you know well in advance what the tax brackets will be when you file your taxes. However, 2017 is an unusual case, because some believe that tax reform could change the tax structure between now and the end of the year.

Nevertheless, the 2017 tax brackets are available as defined under current law, and especially because many think that any changes to taxes will apply only in 2018 or later, using these brackets as a starting point is a good move. So, without further ado, here are the 2017 tax brackets for planning purposes.

Tax forms with calculator and eyeglasses.

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2017 tax brackets for singles

Any unmarried person can file as single, and it's the only permissible option if you don't qualify for the more beneficial filing statuses as a head of household or a qualifying widow or widower. The brackets are as follows:

Bracket

Tax is this amount plus this percentage

Of the amount over

$0 to $9,325

$0 plus 10%

$0

$9,325 to $37,950

$932.50 plus 15%

$9,325

$37,950 to $91,900

$5,226.25 plus 25%

$37,950

$91,900 to $191,650

$18,713.75 plus 28%

$91,900

$191,650 to $416,700

$46,643.75 plus 33%

$191,650

$416,700 to $418,400

$120,910.25 plus 35%

$416,700

above $418,400

$121,505.25 plus 39.6%

$418,400

Data source: IRS.

2017 tax brackets for heads of household

If you're single but support a child, parent, or other relative who meets certain qualifications, then you're allowed to file as a head of household. Qualifying persons have to live with you more than half the year, and it's often necessary that you be able to claim them as dependents. As you can see below, the brackets are higher and wider than for single filers, resulting in tax savings.

Bracket

Tax is this amount plus this percentage

Of the amount over

$0 to $13,350

$0 plus 10%

$0

$13,350 to $50,800

$1,335 plus 15%

$13,350

$50,800 to $131,200

$6,952.50 plus 25%

$50,800

$131,200 to $212,500

$27,052.50 plus 28%

$131,200

$212,500 to $416,700

$49,816.50 plus 33%

$212,500

$416,700 to $444,550

$117,202.50 plus 35%

$416,700

above $444,550

$126,950 plus 39.6%

$444,550

Data source: IRS.

2017 tax brackets for married joint filers

The vast majority of those who are married file jointly. The brackets below apply to them, as well as to qualifying widows and widowers.

Bracket

Tax is this amount plus this percentage

Of the amount over

$0 to $18,650

$0 plus 10%

$0

$18,650 to $75,900

$1,865 plus 15%

$18,650

$75,900 to $153,100

$10,452.50 plus 25%

$75,900

$153,100 to $233,350

$29,752.50 plus 28%

$153,100

$233,350 to $416,700

$52,222.50 plus 33%

$233,350

$416,700 to $470,700

$112,728 plus 35%

$416,700

above $470,700

$131,628 plus 39.6%

$470,700

Data source: IRS.

2017 tax brackets for married separate filers

Married couples can choose to file separately, but it typically results in more tax. However, for some, there are special factors that make filing separately a smarter move. The brackets are below.

Bracket

Tax is this amount plus this percentage

Of the amount over

$0 to $9,325

$0 plus 10%

$0

$9,325 to $37,950

$932.50 plus 15%

$9,325

$37,950 to $76,550

$5,226.25 plus 25%

$37,950

$76,550 to $116,675

$14,876.25 plus 28%

$76,550

$116,675 to $208,350

$26,111.25 plus 33%

$116,675

$208,350 to $235,350

$56,364 plus 35%

$208,350

above $235,350

$65,814 plus 39.6%

$235,350

Data source: IRS.

2 things to keep in mind about tax brackets

These are a couple of areas in which people get confused with tax brackets. First, the tax bracket that you're in doesn't necessarily apply to all of your income. For instance, if you're single with taxable income of $40,000, you're in the 25% bracket. But you only paid tax at a 25% rate on the last $2,050 you earned. The rest got taxed at lower rates of 10% or 15%.

Also, keep in mind that the starting point for these brackets is taxable income, and that's typically much different from your gross income from all sources. In particular, taxable income takes your personal exemptions into account, as well as either the standard deduction or your itemized deductions.

Still, knowing your tax bracket can give you valuable information for your tax planning. Because your tax bracket also applies to any additional income you would earn -- until you move into the next higher bracket, of course -- then you can judge how much you could boost your take-home pay by working harder and earning more money. Moreover, if tax reform does come sooner rather than later, then you'll have a better idea of whether new laws will leave you better off, worse off, or in roughly the same position as before.

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