Colorado Tax Filing

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How to File Your Colorado Taxes

Important fact: In Colorado, all residents pay the same flat rate on their income: 4.63 percent. In some special cases (depending on budget targets), the rate may be lowered to 4.5 percent.

You can file your taxes electronically in Colorado, in two different ways: by using an online system called NetFile or by using a touch-tone telephone system called TeleFile. These systems are accessible on a non-stop basis, and most of Colorado’s taxpayers are eligible to use them.

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Colorado Tax Forms

Determine Your Residency Status

The amount of your taxes depends on your residency status, so check below to see which category you fall in.

You Are a Resident of Colorado

Colorado has a special way of defining residents. If you had your domicile home or lived in Colorado for at least 183 days of the tax year, you are a resident. In this case, you have to file an income tax return by using Form-104. You can download the 2019 Colorado Income Tax Guide above for more information on how to file Form-104.

The tax filing system in Colorado is based on the federal one, so there are no other credits or exceptions than those already stated on your federal return. When filling in Form-104, you will need to perform some calculations based on your federal taxable income; the result will be taxed by Colorado at a flat rate of 4.63%.

You Are a Part-Year Resident in Colorado

If you moved to or left Colorado during the tax year, you are considered a part-year resident. In this case, if you filed a federal tax-return, you may have to file a tax return with the state of Colorado as well. For special cases, see sections “You Are a Colorado Resident”, “You Are a Colorado Resident Who Works in a Different State”, “You Are a Nonresident Who Works in Colorado” or “You are a nonresident who sold property in Colorado” to determine which forms you need to file.

You Are a Colorado Resident Who Works in a Different State

If you are a resident working in a different state, you have to keep in mind a few things in order to avoid dual taxation. First, you need to file your federal tax return the same way as if you were a resident living and working in Colorado. Second, file your tax return with the state where you are working. Third, file your Colorado tax return. To do that, fill in Colorado Form 104 (lines 1-18 only). Then, fill Colorado Form 104CR (lines 20, 21 and 24 only).

You are a nonresident who works in Colorado

If you didn’t have your domicile home in Colorado for any part of the tax year, even if you may temporarily reside or work here, you are considered a nonresident of Colorado. When are you required to file a Colorado nonresident return? If you filed a federal income return which included income obtained from a source in Colorado (including property sales), or you have a Colorado tax liability. You should keep in mind that there is no minimum taxable income limit. To file your nonresident Colorado return, you have to use Form-104PN.