Colorado taxes for early retirees: mountains, a flat tax and surprise refunds

By Tom, CPA · Updated October 25, 2026

TL;DR: Colorado taxes income at a flat 4.40%. From age 55, retirees can subtract up to $20,000 of pension and annuity income ($24,000 at 65+), but early IRA distributions don't qualify. Social Security is fully subtractable at 65+, and at 55 to 64 if AGI is $75,000 or less ($95,000 joint). TABOR refunds may arrive when state revenue exceeds its cap.

Educational only, not tax, legal, or investment advice. Examples are illustrations, not predictions. Rules and limits change; verify current figures and talk to a qualified professional about your situation.

Colorado's tax system has a flat rate, age-based subtractions for retirement income, and a constitutional quirk called TABOR that sometimes mails money back to taxpayers. For early retirees, the age thresholds are the part to study: at 55 and at 65, the rules change in your favor.

This guide walks through each piece and ends with a worked example for a FIRE household that retires before 55.

CPA Warning Label: Altitude may affect baking times, lung capacity and how quickly your eyes glaze over reading subtraction rules.

Flat rate (verify)

Colorado taxes individual income at a flat rate of 4.40%, per the Department of Revenue's individual income tax guide, applied to federal taxable income after Colorado additions and subtractions. Because Colorado starts from federal taxable income, the federal standard deduction effectively flows through, which keeps the state bill low for modest incomes.

The rate has been temporarily reduced in some years when revenue triggers were met, so check the DOR's current-year instructions before filing.

Pension/annuity subtraction by age

Colorado's pension and annuity subtraction, per the DOR:

Qualifying income generally includes pensions, annuities and IRA distributions, but the DOR notes that distributions that are premature (generally those subject to the federal early withdrawal rules) don't qualify. So a 56-year-old taking a penalty-exempt 72(t) or rule-of-55 distribution should read the instructions carefully, because "premature" is the operative word.

Each spouse claims their own subtraction based on their own age and income.

Social Security treatment

Colorado's Social Security subtraction is generous for older retirees and income-tested for younger ones:

• 65 and older: all Social Security included in federal taxable income can be subtracted.
• 55 to 64: full subtraction if AGI is $75,000 or less ($95,000 for joint filers). Above that, Social Security shares the $20,000 limit with pension income.

Most FIRE retirees won't claim Social Security before 62, so the 55 to 64 rule mainly matters for someone receiving disability or survivor benefits, or claiming at 62 to 64.

TABOR refunds

Colorado's Taxpayer's Bill of Rights (TABOR) limits how much revenue the state can keep. When revenue exceeds the limit, the excess is refunded to taxpayers through mechanisms set by law, which have included temporary rate cuts, sales tax refunds and flat per-filer refunds. The amount and method change from year to year and depend on the state budget.

For planning, treat TABOR refunds as a pleasant surprise, not income. Some refund methods require filing a Colorado return even if you otherwise wouldn't need to, which matters for early retirees with very low income. Read the DOR's current TABOR instructions each year. Lavish Larry spends his refund before it arrives. Frugal Fran deposits hers and then forgets about it, which is the most Fran thing imaginable.

Example

Illustration. Hypothetical married couple who retire at 50 in Colorado, with $1.5 million in traditional IRAs and a taxable account.

• Ages 50 to 54: they do $50,000 Roth conversions each year. No pension subtraction applies before 55. Colorado tax is 4.40% of their federal taxable income: after the 2026 federal standard deduction ($32,200), about $17,800 is taxable, or roughly $780.
• Ages 55 to 64: regular IRA distributions (not premature ones) may qualify for up to $20,000 of subtraction each, or $40,000 combined. Conversions are trickier: check whether the DOR treats them as qualifying distributions for your situation before relying on it.
• 65 and older: the subtraction rises to $24,000 each, and all Social Security is subtractable.

Because Colorado piggybacks on federal taxable income, anything that lowers federal taxable income, such as HSA contributions, traditional IRA contributions from part-time wages or the federal standard deduction, lowers the Colorado bill too. That's a nice simplifier compared with states that ignore federal rules.

Bottom line: Colorado's bill for a moderate-income early retiree is often a few hundred to a couple thousand dollars a year.

Common Colorado mistakes

• Claiming the pension subtraction on premature distributions.
• Forgetting each spouse's subtraction depends on their own age.
• Not filing a return in a year when filing is needed to get a TABOR refund.
• Ignoring high property values and insurance costs in mountain towns.
• Treating a temporary rate cut as permanent in a long-range plan.

Moving to or from Colorado

Colorado taxes residents on all of their income and nonresidents generally only on income from Colorado sources. In the year you move, you'll usually file as a part-year resident and split income by date. Retirement account withdrawals and investment income generally follow your residence on the date you receive them, so the timing of a big Roth conversion or sale relative to the move can change which state taxes it.

Make the move clean: driver's license, vehicle and voter registration, mailing address, doctors and banks should all point to the same place. States you leave may look closely at where you spend your time and where your closest ties are. See changing state tax residency.

Federal taxes still apply

Whatever Colorado does, the federal system still sets the base. For 2026 the federal standard deduction is $16,100 for single filers and $32,200 for married couples filing jointly, and long-term capital gains can fall in a 0% bracket at lower incomes. Many early retirees aim to fill the low federal brackets each year with Roth conversions or gain harvesting. State tax then rides on top, so check how Colorado treats each type of income before deciding how much to convert. Social Security can become partly taxable federally as other income rises, and Medicare premiums later depend on income from two years earlier. A year of very low income can be just as wasteful as a year of very high income, because unused low brackets disappear on December 31. See 2026 tax brackets for FIRE.

Health coverage before Medicare

Before Medicare at 65, most early retirees in Colorado buy coverage through the ACA Marketplace (HealthCare.gov or the state exchange). Premium tax credits depend on household income, so the same withdrawal choices that drive Colorado income tax also drive what you pay for insurance. Price plans for your actual county, since insurer choice and premiums vary a lot between metro and rural areas. If your taxable income will be very low, check Medicaid eligibility rules for Colorado too. Our guides to the ACA subsidy cliff and managing MAGI go deeper.

One practical tip: estimate next year's income before open enrollment, then pick withdrawals to land where you planned. Surprises in either direction get reconciled on your federal return, and from 2026 there is no cap on repaying excess advance credits.

Your Colorado planning checklist

Use this as a starting list when you are weighing a move or planning withdrawals. Work through it a year before you leave your job, and again each fall before you decide on Roth conversions.

• Note when each spouse turns 55 and 65; plan IRA distributions around those dates.
• Confirm whether a distribution is 'premature' before claiming the subtraction.
• Check the current-year rate and TABOR refund rules on the DOR site.
• Compare property taxes and insurance in your target county.

Tax rules change every legislative session. Confirm current figures with the Colorado revenue department before acting, and treat this page as education, not advice for your situation.