Guides
Capital Gains Tax on a Home Sale Explained
How the Section 121 exclusion shelters gain on a primary residence sale, and what happens when a property does not fully qualify as a primary residence.
Service Overview
How this service works
Capital gains tax on a home sale works differently than tax on a rental or investment property, because a primary residence benefits from the Section 121 exclusion. A single filer can exclude up to two hundred fifty thousand dollars of gain, and a married couple filing jointly can exclude up to five hundred thousand dollars, as long as the ownership and use tests are met. Those tests require the owner to have owned the home and used it as a primary residence for at least two of the five years before the sale.
Gain above the exclusion amount is taxed at long term capital gains rates if the home was held more than one year, generally zero, fifteen, or twenty percent federally based on income, plus the three point eight percent net investment income tax for higher earners. Colorado, CO homeowners also owe state income tax on any gain above the exclusion, since Colorado taxes capital gain as ordinary income under its flat rate. For most Denver, CO homeowners selling a primary residence at a typical appreciation level, the Section 121 exclusion covers the entire gain, and no federal or state capital gains tax is owed.
The exclusion does not apply to gain attributable to periods of nonqualified use, such as time the home was rented out before it became a primary residence, and it does not apply if the home was never actually used as a primary residence. A straight rental property sale does not qualify for Section 121 at all, which is why the distinction between a home sale and an investment property sale matters for tax planning.
Homeowners who have used part of the property for a home office or rented out a portion, such as a basement unit or an accessory dwelling, may need to allocate the gain between the excludable personal use portion and a taxable business or rental use portion. Depreciation claimed on any business or rental portion is still subject to recapture even when the home otherwise qualifies for Section 121.
A 1031 exchange is not available for a straight primary residence sale, since the property is not held for investment or business use. Homeowners considering converting a residence to a rental before selling, or investors who inherited a family home and are deciding what to do with it, should evaluate the combined use of the Section 121 exclusion and a later 1031 exchange separately, since the rules for each apply to different portions of the property's history.
Service Details
What is included
Comprehensive support to keep your exchange compliant and on schedule.
Explanation of the Section 121 ownership and use tests
Calculation of exclusion amounts for single and joint filers
Review of how nonqualified use and business or rental use portions affect the exclusion
Clarification of why a 1031 exchange does not apply to a straight primary residence sale
Guidance for homeowners converting a residence to a rental or vice versa
Explanation of depreciation recapture on any business or rental portion of a home
Common Scenarios
When this service helps
A Denver homeowner is selling a longtime primary residence and wants to confirm the Section 121 exclusion covers the full gain.
A Colorado Springs homeowner rented a basement unit for several years and wants to understand how that affects the exclusion.
A Boulder homeowner is deciding whether to sell a family home outright or convert it to a rental before selling.
Example Project
Home Sale Capital Gains Guidance
Example of the type of engagement we can handle
Client Situation
Homeowner in Denver is selling a primary residence that included a rented basement unit for several years and wants to understand the tax treatment.
Our Approach
We review the ownership and use history, calculate the personal use and rental use allocation, estimate the Section 121 exclusion available, and identify any depreciation recapture on the rental portion.
Expected Outcome
Homeowner understands how much of the gain is excludable, what portion may be taxable, and what documentation supports the allocation.
Educational content only. Not tax, legal, or investment advice. A 1031 exchange defers income tax on qualifying real property and does not remove transfer or documentary taxes.
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The Qualified Intermediary Role Explained
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Common Questions
Frequently asked questions
How much capital gains tax exclusion does a Denver, CO homeowner get on a primary residence sale?
A single filer can exclude up to two hundred fifty thousand dollars of gain, and a married couple filing jointly can exclude up to five hundred thousand dollars, provided the home was owned and used as a primary residence for at least two of the five years before the sale. Gain above those amounts is taxed at capital gains rates.
Can a Denver, CO homeowner use a 1031 exchange on a primary residence sale?
No. A 1031 exchange requires the relinquished property to be held for investment or business use, and a primary residence does not meet that standard. The Section 121 exclusion is the relevant tax benefit for a primary residence sale, not a 1031 exchange.
What happens if a Denver, CO homeowner rented out part of the house before selling?
Gain attributable to a rental or business use portion of the home, and any depreciation claimed on that portion, generally does not qualify for the Section 121 exclusion and may be subject to depreciation recapture. The personal use portion can still qualify for the exclusion if the ownership and use tests are met.
Does a Denver, CO homeowner need to reinvest the proceeds from a home sale to get the Section 121 exclusion?
No. Unlike a 1031 exchange, the Section 121 exclusion does not require reinvesting the sale proceeds into another home. The exclusion applies automatically to qualifying gain regardless of what the homeowner does with the proceeds afterward.
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