Do You Pay Capital Gains Tax When Selling a House in Colorado?

The short answer

Do you pay capital gains tax when selling a house in Colorado? Often, no, if the home is your main residence and you meet the IRS ownership and use tests. Under IRS Topic no. 701 (updated September 24, 2026), you may be able to exclude up to $250,000 of gain, or up to $500,000 if you file a joint return with your spouse. Gain that is excluded federally is generally not taxed by Colorado either, because Colorado starts from federal taxable income.

When tax does show up, it is usually because the gain is larger than the exclusion, the home was a rental or second home, depreciation was taken in earlier years, or the seller is a nonresident facing Colorado’s real-estate withholding at closing. I’m not a tax advisor, and this isn’t tax or legal advice. Treat this as a map of questions to bring to a CPA before you list.

How your gain is calculated

Capital gains tax starts with a simple formula from IRS Publication 523, Selling Your Home: selling price minus selling expenses equals the amount realized; subtract your adjusted basis, and the result is your gain or loss. A positive number is a gain. A personal-residence loss is generally not deductible.

Adjusted basis usually starts with what you paid for the home, then moves with events during ownership. Additions and improvements that add value or prolong the home’s life, such as a bedroom addition, a new roof, a heating system or built-in appliances, typically increase basis. Ordinary maintenance, such as painting or fixing a leak on its own, generally does not. If you ever claimed depreciation for a home office or a period when the home was rented, that usually reduces basis and can create taxable gain even when the rest of the sale qualifies for the exclusion.

This is why I ask sellers to pull closing statements from when they bought, a list of major projects with invoices, and any depreciation schedules before we talk net proceeds. My guide to the cost to sell a house in Colorado covers the closing-cost side of that net sheet; capital gains sit beside those costs, not inside them.

The federal home-sale exclusion

The exclusion most Colorado primary-home sellers rely on is often called the Section 121 exclusion. Per IRS Topic 701:

• Ownership test. You (or your spouse, on a joint return) owned the home for at least 24 months out of the five years ending on the sale date.
• Use test. You used the home as your main home for at least 24 months out of those same five years. On a joint return, both spouses generally must meet the use test.
• Look-back. You generally cannot claim the exclusion if you already excluded gain from another home sale in the two years before this one.

Ownership and use periods can be different stretches inside the five-year window. Military, Foreign Service and intelligence community members on qualified official extended duty may be able to suspend the five-year test period for up to ten years. Publication 523 also describes reduced (partial) exclusions when you sell earlier because of a work-related move, health reasons or certain unforeseen circumstances. Those rules are fact-specific; a CPA should apply them to your timeline.

If you receive Form 1099-S, Proceeds From Real Estate Transactions, or you cannot exclude all of the gain, the sale generally needs to be reported, typically on Form 8949 and Schedule D. Receiving a 1099-S does not automatically mean you owe tax.

What Colorado taxes

Colorado does not offer its own home-sale exclusion on top of the federal one. The Colorado Department of Revenue’s Individual Income Tax Guide (revised January 2026) explains that Colorado individual income tax is generally based on federal taxable income, with state modifications. So when the federal exclusion removes gain from federal taxable income, that gain typically never reaches your Colorado return either.

Gain that remains taxable is different. Federally, long-term capital gains on a home held more than a year can be taxed at preferential rates (for tax years beginning in 2025, IRS Topic 409 describes 0%, 15% and 20% brackets that depend on taxable income). Colorado does not mirror that preference. It taxes Colorado taxable income at a flat rate; the January 2026 guide lists 4.4% for tax year 2025 (and 4.25% for 2024). The rate can change by year under state law, so confirm the rate for the year you close.

Colorado also has a capital-gain subtraction that sounds helpful and usually is not, for a typical home sale. According to the Department’s June 2024 publication Income Tax Topics: Colorado Capital Gain Subtraction, for tax years beginning on or after January 1, 2022, the subtraction is available only to taxpayers required to file IRS Schedule F, and only for qualifying agricultural real property. A residential sale in Denver, Lakewood, Castle Pines, Highlands Ranch, Parker, Castle Rock or Broomfield does not qualify.

Colorado withholding for nonresident sellers

Separate from whether you ultimately owe tax, Colorado can require money to be withheld at closing when a nonresident sells Colorado real estate. The closing company’s instructions on form DR 1083 (revised October 1, 2025) and related statute describe the basics:

• Withholding generally applies to nonresident transferors when the sales price is more than $100,000.
• The amount is the lesser of 2% of the sales price or the net proceeds otherwise due to the seller.
• Withheld amounts are remitted with form DR 1079 and claimed as a credit on the seller’s Colorado income tax return for that year.

Exceptions exist. The withholding agent may rely in good faith on a written affirmation that the transferor is a Colorado resident, that the property was the transferor’s principal residence (the affirmation references the IRC Section 121 exclusion), that the transferor reasonably expects to owe no Colorado income tax on the gain, or that another listed exception applies. If you are moving out of state and selling your Colorado home, tell your title company and CPA early so the right box on DR 1083 is checked and you are not surprised at the signing table. This withholding is a prepayment toward Colorado tax, not an extra tax on top of your final bill.

When sellers more often owe tax

In the markets I work, these are the situations that most often need a CPA conversation before the listing goes live:

• Long-held homes with large appreciation. A couple who bought decades ago in a neighborhood that has moved up sharply can clear the $500,000 joint exclusion even after counting improvements.
• Rental or mixed use. Time as a rental, a home office with depreciation, or a basement apartment treated as business use can create taxable pieces, including depreciation that cannot be excluded.
• Second homes and investment property. The Section 121 exclusion is for a main home. A mountain condo or a long-term rental is a different analysis; some investors ask a CPA about a like-kind exchange under different rules.
• Inherited property. Basis rules for inherited homes differ from a home you bought, and Publication 523 walks through several inheritance scenarios. Bring the estate paperwork to your CPA.
• Selling sooner than two years. A job move, health change or other unforeseen event may support a partial exclusion; it is not automatic.

If you are weighing a sale against keeping the home as a rental instead, my sell or rent guide covers the practical tradeoffs. The tax side of that choice belongs with your CPA.

What to gather before you list

You do not need a finished tax projection to put a home on the market, but the sellers who feel calm at closing usually collected these early:

1. Purchase closing statement and any documents showing your original basis.
2. Improvement file with invoices for additions, major systems, roofing, kitchen or bath remodels and other basis-building work.
3. Depreciation history if the home was ever rented or used partly for business.
4. Prior-year tax returns that already reported housing-related deductions.
5. Residency plans after closing, so title can handle DR 1083 correctly if you are leaving Colorado.

That file sits beside the prep work I cover in how to sell a luxury home in Denver and the seasonal timing in the best time to sell a house in Denver. If you are moving to something smaller, the tax section of my downsizing guide pairs with this one.

Selling across the Denver metro

The federal and Colorado rules are statewide. What changes by neighborhood is the size of the potential gain and the paperwork around the property: HOA and metro district documents in places like Highlands Ranch or Anthem Ranch in Broomfield, older mechanical systems in central Denver, foothills wells and septic in parts of Jefferson and Douglas Counties, and layered associations in Castle Pines. I help sellers in Denver, Lakewood, Castle Pines, Highlands Ranch, Parker and Castle Rock build a net sheet first, then bring the tax questions to their CPA with clean numbers.

How I help

I grew up in Castle Rock and work with sellers across Denver, Lakewood, Castle Pines, Highlands Ranch, Parker, Castle Rock and Broomfield. I work with Sean Gribbons at The Gold Standard Brokerage; Sean founded the brokerage, and we run it together. I will not prepare your tax return, but I will help you estimate sale proceeds, organize the property file a CPA needs, and time the listing around your move. Start with the “What’s my home worth?” tool, call or text me at 720-357-5785, or use the inquiry form on this page.