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How do home improvements increase my cost basis?

Home Buyingintermediate3 answers · 5 min readUpdated February 28, 2026

Quick Answer

Home improvements that add value, prolong your home's useful life, or adapt it to new uses increase your cost basis dollar-for-dollar. If you bought a home for $300,000 and spent $50,000 on qualifying improvements, your cost basis becomes $350,000, potentially saving you $7,500-$11,100 in capital gains tax when you sell.

Best Answer

RK

Robert Kim, CPA

Best for homeowners who have made improvements and want to minimize capital gains tax

Top Answer

How home improvements increase your cost basis


Your cost basis is your original purchase price plus qualifying improvements minus depreciation. When you sell your home, you pay capital gains tax on the profit (sale price minus cost basis). Every dollar you add to your cost basis through improvements reduces your taxable gain by one dollar.


According to IRS Publication 523, qualifying improvements must:

  • Add value to your home
  • Prolong your home's useful life
  • Adapt your home to new uses

  • These improvements become part of your cost basis and reduce capital gains tax when you sell.


    Example: $50,000 kitchen renovation saves $11,100 in taxes


    Let's say you bought a home in 2020 for $300,000 and spent $50,000 on a kitchen renovation in 2022. You sell in 2026 for $500,000.


    Without improvement cost basis:

  • Sale price: $500,000
  • Original cost basis: $300,000
  • Capital gain: $200,000
  • Less Section 121 exclusion: $250,000 (married filing jointly)
  • Taxable gain: $0

  • But what if your gain exceeds the exclusion? Let's say you sell for $650,000:


    Without improvement cost basis:

  • Capital gain: $350,000
  • Less Section 121 exclusion: $250,000
  • Taxable gain: $100,000
  • Tax owed (22% bracket): $22,200

  • With improvement cost basis:

  • Sale price: $650,000
  • Cost basis ($300,000 + $50,000): $350,000
  • Capital gain: $300,000
  • Less Section 121 exclusion: $250,000
  • Taxable gain: $50,000
  • Tax owed (22% bracket): $11,100
  • Tax savings: $11,100

  • What qualifies as a cost basis improvement


    Qualifying improvements (add to cost basis):

  • Kitchen or bathroom renovations
  • Adding rooms, decks, or garages
  • New roof, siding, or windows
  • HVAC system installation/replacement
  • Flooring replacement (not refinishing)
  • Swimming pools or permanent landscaping
  • Electrical or plumbing upgrades
  • Energy-efficient improvements (solar panels, insulation)

  • Non-qualifying expenses (cannot add to cost basis):

  • Routine maintenance and repairs
  • Painting (unless part of larger renovation)
  • Fixing broken items
  • Lawn mowing or seasonal maintenance

  • Key factors that maximize your tax benefit


  • Keep detailed records: Save all receipts, contracts, and permits for improvements
  • Timing matters: Improvements made while you own the home count toward basis
  • Professional installation: Both materials and labor costs count toward basis
  • Quality improvements: Focus on improvements that genuinely add value

  • What you should do


    Review your home improvement history and gather documentation for all qualifying improvements. Many homeowners have $20,000-$100,000 in improvements they haven't properly tracked for tax purposes. Use our return scanner to identify potential missed cost basis additions from previous years.


    Key takeaway: Every $1,000 in qualifying home improvements reduces your capital gains tax by $220-$370 (depending on your tax bracket), making proper record-keeping worth thousands in tax savings.

    *Sources: [IRS Publication 523](https://www.irs.gov/pub/irs-pdf/p523.pdf), [IRS Publication 551](https://www.irs.gov/pub/irs-pdf/p551.pdf)*

    Key Takeaway: Home improvements that add value increase your cost basis dollar-for-dollar, potentially saving $220-$370 in capital gains tax per $1,000 spent on qualifying improvements.

    Tax impact of improvements by property type and tax situation

    Property TypeCost Basis BenefitAdditional BenefitsTax Rate on Gains
    Primary residenceReduces capital gainsMay qualify for $250K/$500K exclusion15-20%
    Investment propertyReduces capital gains + annual depreciationDepreciation deductions25% (recapture) + 15-20% (gains)
    Inherited propertyAdds to stepped-up basisNo depreciation recapture15-20%

    More Perspectives

    MW

    Michelle Woodard, JD

    Best for investors managing multiple properties and rental income

    Cost basis for investment properties


    For rental properties, cost basis calculations are more complex because you can depreciate the property annually but must recapture that depreciation when you sell. According to IRS Publication 527, improvements to rental property increase your depreciable basis, allowing you to claim larger annual depreciation deductions.


    Investment property example


    You buy a rental property for $400,000 (land: $100,000, building: $300,000) and spend $30,000 on improvements. Your new depreciable basis becomes $330,000 ($300,000 + $30,000). Over 27.5 years, this generates an additional $1,091 in annual depreciation deductions ($30,000 ÷ 27.5 years).


    When you sell, both the original building and improvements are subject to depreciation recapture at 25%, but any gain above your adjusted basis is taxed at capital gains rates (15-20%).


    Key differences for investors


    Immediate benefits: Unlike primary residences, investment property improvements generate annual depreciation deductions

    Recapture considerations: All depreciation taken must be recaptured at 25% when you sell

    1031 exchanges: Cost basis carries forward in like-kind exchanges, preserving improvement values


    Key takeaway: Investment property improvements provide dual benefits—immediate depreciation deductions plus increased cost basis to reduce capital gains tax at sale.

    Key Takeaway: Investment property improvements provide both annual depreciation deductions and increased cost basis, offering dual tax benefits for rental property owners.

    RK

    Robert Kim, CPA

    Best for heirs who inherited property and made improvements before selling

    Cost basis for inherited property improvements


    When you inherit a home, you receive a "stepped-up basis" equal to the fair market value on the date of death. Per IRS Publication 551, any improvements you make after inheriting the property are added to this stepped-up basis.


    Inherited property example


    You inherit a home worth $450,000 (stepped-up basis). You spend $25,000 on improvements and sell for $550,000 two years later.


    Your tax calculation:

  • Sale price: $550,000
  • Cost basis ($450,000 + $25,000): $475,000
  • Capital gain: $75,000
  • Tax owed (20% rate, high-income): $15,000

  • Without tracking improvements:

  • Capital gain would be: $100,000
  • Tax owed: $20,000
  • Tax savings from improvements: $5,000

  • Special considerations for inherited property


    No Section 121 exclusion: The $250,000/$500,000 home sale exclusion requires living in the home for 2 of the last 5 years

    State estate taxes: Some states don't provide stepped-up basis, making improvement tracking more critical

    Multiple heirs: Document who paid for improvements if ownership is shared


    Key takeaway: Improvements to inherited property increase your already-favorable stepped-up basis, providing additional tax savings when you sell.

    Key Takeaway: Improvements to inherited property add to your stepped-up basis, providing additional tax savings beyond the already-favorable inheritance tax treatment.

    Sources

    cost basishome improvementscapital gainstax savings

    Reviewed by Robert Kim, CPA on February 28, 2026

    This content is for educational purposes only and is not a substitute for professional tax advice. Consult a qualified tax professional for advice specific to your situation.

    How Do Home Improvements Increase Cost Basis? | MissedDeductions