Selling a Home Used Partly for Business: How the Home Office Affects Your Exclusion

By Yarik Yarosh, CPA ·September 5, 2026 ·8 min read

Written by Yarik Yarosh, CPA (US & Canada) September 5, 2026 · FL CPA license AC61704 · CPA Ontario

Selling a home that has been used partly for business creates a tax question that surprises many owners: does the home office disqualify part of the gain from the $250,000/$500,000 exclusion under IRC 121? The answer depends on two factors: where the office was located (inside the home vs. a separate structure) and whether depreciation was claimed. For offices within the home (a dedicated room or area), the IRS simplified the rules starting in 2003: the entire home, including the office portion, qualifies for the Section 121 exclusion, BUT depreciation allowed or allowable after May 6, 1997 must be recaptured as unrecaptured Section 1250 gain at a maximum 25% rate. For offices in a separate structure (a detached building), the business portion is treated as a different property and doesn’t qualify for the exclusion at all, meaning you must allocate the gain and pay capital gains tax on the business portion. The simplified home office deduction method ($5/sq ft, max 300 sq ft) claims zero depreciation, so choosing that method eliminates the recapture problem entirely.

✓Key takeaway

Home sale with business use, rules summary:

Office Location	IRC 121 Exclusion	Depreciation Recapture
Within the home (room, area)	Full gain eligible for exclusion	Must recapture depreciation taken after 5/6/1997 at max 25%
Separate structure (detached building)	Business portion doesn’t qualify for exclusion	Full gain on business portion taxable (LTCG + depreciation recapture)

IRC 121 basic requirements:

Requirement	Rule
Ownership test	Owned the home for at least 2 of the last 5 years
Use test	Used as principal residence for at least 2 of the last 5 years
Exclusion amount	$250,000 (single), $500,000 (MFJ)
Frequency	Generally once every 2 years

Depreciation recapture on home office (within the home):

Element	Details
What’s recaptured	Depreciation allowed or allowable after May 6, 1997
Tax rate on recapture	Maximum 25% (unrecaptured Section 1250 gain)
“Allowable” means	Even if you did NOT claim the depreciation, you must recapture it if you were entitled to it
Simplified method users	$0 depreciation claimed = $0 recapture

How does a home sale work with a home office?

Hypothetical example

Round numbers. A single taxpayer bought a home for $400,000 in 2015 and has used 15% of it (300 sq ft of a 2,000 sq ft home) as a home office since 2016. The taxpayer sells in 2025 for $700,000.

Home office depreciation history (actual method):

Year	Business %	Depreciable Basis (15% of $400K = $60K, net of land)	Annual Depreciation (39-year residential)
2016-2025 (10 years)	15%	$48,000 (building only, excluding land at 20% of price)	$48,000 / 39 = $1,231/year
Total depreciation (10 years)			$12,310

Gain calculation:

Item	Amount
Sale price	$700,000
Original cost	$400,000
Depreciation claimed (home office)	($12,310)
Adjusted basis	$387,690
Total gain	$312,310

Tax on the sale (office WITHIN the home):

Component	Amount	Tax
Depreciation recapture (post-5/6/1997)	$12,310	25% = $3,078
Remaining gain ($312,310 - $12,310)	$300,000	$0 (excluded under IRC 121, under $250K limit… wait)

The remaining gain is $300,000, which exceeds the $250,000 single exclusion by $50,000:

Component	Amount	Tax
Depreciation recapture	$12,310	25% = $3,078
Gain excluded under IRC 121	$250,000	$0
Gain exceeding exclusion	$50,000	15-20% LTCG = $7,500-$10,000
Total tax		$10,578-$13,078

Same scenario, married filing jointly ($500,000 exclusion):

Component	Amount	Tax
Depreciation recapture	$12,310	25% = $3,078
Remaining gain	$300,000	$0 (under $500K MFJ exclusion)
Total tax		$3,078

The only tax is the $3,078 depreciation recapture. The MFJ exclusion covers all remaining gain.

Same scenario using the simplified home office method:

Component	Amount	Tax
Depreciation claimed	$0 (simplified method takes no depreciation)
Total gain	$300,000 ($700K - $400K, no depreciation adjustment)
Depreciation recapture	$0
Gain excluded (MFJ)	$300,000	$0
Total tax		$0

The simplified method eliminates all recapture. The tradeoff: $1,500/year maximum deduction vs. potentially higher actual deductions, but zero recapture at sale.

Separate structure scenario (detached office building): If the office was in a separate detached building (15% of total property value):

Component	Amount
Sale price allocated to separate office (15% x $700K)	$105,000
Basis allocated to separate office (15% x $400K)	$60,000
Depreciation on separate office	($12,310)
Adjusted basis of separate office	$47,690
Gain on separate office	$57,310

Tax Component	Amount	Tax
Depreciation recapture (25%)	$12,310	$3,078
Remaining gain on office (LTCG, 15%)	$45,000	$6,750
Personal residence gain (85% x $700K - 85% x $400K)	$255,000	$0 (excluded)
Total tax		$9,828

The separate structure costs $6,750 MORE in tax than the within-the-home office because the business portion’s gain can’t be excluded.

Decision matrix:

Factor	Simplified Method	Actual Method (Within Home)	Separate Structure
Annual deduction	$1,500 max	Actual expenses x business % (often $3,000-$8,000+)	Actual expenses (full building costs)
Depreciation claimed	$0	$1,200+/year	$1,200+/year
Recapture at sale	$0	25% on total depreciation	25% on total depreciation
IRC 121 exclusion	Full gain eligible	Full gain eligible (minus recapture)	Business portion excluded from IRC 121
Best for	Homeowners planning to sell within 5-10 years	Homeowners in expensive homes, not selling soon	Rare (only when separate structure deductions are very high)

The “allowable” trap: Even if you DID NOT claim depreciation on your home office (you forgot, or you chose not to), the IRS taxes you as if you did. “Depreciation allowed or allowable” means the IRS will recapture depreciation you were entitled to take, whether you actually took it or not. The only defense is to have had no home office deduction at all (no Form 8829 filed) or to have used the simplified method (which explicitly takes $0 depreciation).

This means filing a home office deduction using the actual method and then “skipping” the depreciation line doesn’t avoid recapture. If you were entitled to depreciation and did not take it, you lost the deduction AND will still pay the recapture tax at sale.

Illustrative numbers only, not a real client and not advice for your facts.

What are the two methods for calculating the home office deduction?

The simplified method allows $5 per square foot of your home used for business, up to 300 square feet, for a maximum deduction of $1,500. The regular method calculates actual expenses (mortgage interest or rent, property taxes, utilities, insurance, repairs, depreciation) based on the percentage of your home used exclusively and regularly for business. The regular method requires more recordkeeping but often produces a larger deduction, especially for larger office spaces or expensive homes. Under the regular method, the home office deduction cannot create a business loss, but excess deductions carry forward to the next year. Employees working from home cannot claim the home office deduction under current law (the deduction was suspended for employees by the TCJA through 2025), but self-employed individuals and independent contractors remain eligible.

What expenses qualify under the regular home office deduction method?

Direct expenses (used solely for the office, like painting the office room) are fully deductible. Indirect expenses (benefiting the entire home) are deductible based on the business-use percentage: mortgage interest or rent, property taxes, homeowner’s insurance, utilities, general repairs, and depreciation of the home. The business-use percentage is typically calculated as the square footage of the office divided by total home square footage. Unrelated expenses (like lawn care or kitchen remodeling) are not deductible. The home office deduction cannot create a business loss under the regular method; excess deductions carry forward to future years.

Related guides:

Can you claim a home office deduction if you also rent office space?

Yes, having a separate office doesn’t automatically disqualify your home office deduction as long as your home office meets the regular and exclusive use test under IRC 280A. The home office must be your principal place of business or a place where you regularly meet clients, even if you also maintain another workspace. Under the Soliman test from the Supreme Court decision, a home office qualifies as your principal place of business if you perform substantial administrative or management activities there and have no other fixed location for those activities. The simplified method allows a $5 per square foot deduction up to 300 square feet ($1,500 maximum), while the regular method requires tracking actual expenses and calculating the business-use percentage of your home.

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Cite this page

Yarik Yarosh, CPA. "Selling a Home Used Partly for Business: How the Home Office Affects Your Exclusion." Blue Cloud CPA, September 5, 2026. https://bluecloudcpa.com/guides/small-business-selling-home-used-for-business-tax-rules

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.