Home Office Deduction: Simplified vs. Regular Method (IRC 280A)

By Yarik Yarosh, CPA ·September 5, 2026 ·6 min read

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

The home office deduction under IRC 280A is one of the most underused deductions for self-employed business owners and one of the most misunderstood. The direct deduction (either $1,500 simplified or a portion of actual home expenses) is often modest, but the indirect benefit is significant: having a qualifying home office converts every trip from your home to a work site into a deductible business mile, rather than non-deductible commuting. For a mobile service business owner driving 20,000+ miles per year, this vehicle deduction increase can be worth far more than the home office deduction itself.

✓Key takeaway

Home office deduction requirements:

Exclusive and regular use test:

The space must be used EXCLUSIVELY for business. A desk in the corner of the living room where you also watch TV does not qualify.
The space must be used REGULARLY (not just occasionally). Using a room for business once a month is not regular use.
Exception: storage of inventory or product samples (exclusive use not required if the home is the sole fixed location of the business)
Exception: daycare facilities (exclusive use not required)

Principal place of business test (one of these):

The home office is where you conduct substantial administrative or management activities AND you have no other fixed location where you conduct these activities
OR the home office is where you meet clients/customers in the normal course of business
For mobile service businesses (plumber, notary, locksmith, inspector): the home office qualifies as the principal place of business if you do your admin, scheduling, invoicing, and bookkeeping there

Two methods:

Simplified method:

$5 per square foot of the home office
Maximum 300 square feet ($1,500 maximum deduction)
No depreciation on the home
No recapture when you sell the home
Calculated on Form 8829 or directly on Schedule C

Regular method:

Calculate the business use percentage: office square footage / total home square footage
Apply that percentage to actual home expenses:
Mortgage interest (or rent)
Property taxes
Homeowner’s insurance
Utilities (electricity, gas, water, internet)
Repairs and maintenance (house-wide: prorated; office-specific: 100%)
Depreciation on the home (business use percentage of the building, not land, over 39 years)
Can produce a larger deduction than the simplified method
Triggers depreciation recapture when the home is sold (even if you didn’t claim depreciation, the IRS considers it “allowed or allowable”)

The vehicle mileage benefit (often the bigger win):

Without a home office: trips from home to the first work site and from the last work site to home are PERSONAL commuting (non-deductible)
WITH a qualifying home office: ALL trips between your home office and work sites are BUSINESS miles
For a mobile service business driving 25,000 miles per year, adding 5,000 “commuting” miles as business miles = $3,500 additional deduction at 70 cents/mile

Which method should you use?

Hypothetical example

Round numbers. A self-employed consultant working from home. Home: 2,000 sq ft. Office: 200 sq ft (10% of the home). Annual home expenses:

Expense	Annual Cost	Business (10%)
Mortgage interest	$18,000	$1,800
Property taxes	$6,000	$600
Insurance	$2,000	$200
Utilities	$4,800	$480
Internet	$1,200	$120
General repairs	$2,000	$200
Home depreciation ($300,000 building / 39 years)	$7,692	$769
Total	$41,692	$4,169

Simplified method: 200 sq ft x $5 = $1,000 Regular method: $4,169

Regular method wins by $3,169. However, the regular method:

Requires tracking all home expenses
Triggers depreciation recapture ($769/year accumulates)
Is more complex to calculate

For a 150 sq ft office:

Simplified: 150 x $5 = $750
Regular: 7.5% of expenses = $3,127
Regular still wins

For a 300 sq ft office (simplified max):

Simplified: 300 x $5 = $1,500
Regular: 15% of expenses = $6,254
Regular wins by $4,754

When does simplified win? Almost never on the deduction itself. The simplified method wins on simplicity: no records to keep, no depreciation to track, no recapture at sale. For someone whose regular method deduction would be under $2,000 and who doesn’t want the record-keeping burden, the simplified method is reasonable.

The vehicle mileage impact: Same consultant also drives to client sites. Without a home office, 4,000 miles of “commuting” are non-deductible. With a qualifying home office, those become business miles.

Scenario	Home Office Deduction	Additional Business Miles	Vehicle Deduction Increase	Total Benefit
No home office	$0	0	$0	$0
Simplified	$1,000	4,000	$2,800	$3,800
Regular	$4,169	4,000	$2,800	$6,969

The $2,800 in additional vehicle deduction applies regardless of which home office method is chosen. For mobile service businesses, the vehicle benefit alone justifies claiming the home office deduction.

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:

Home Office Deduction for Small Business Owners: Regular vs Simplified Method
Home Office Deduction for Freelancers: Simplified vs. Actual Method
Home Office Deduction: How to Make It Audit-Proof (Regular Method vs Simplifi…

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. "Home Office Deduction: Simplified vs. Regular Method (IRC 280A)." Blue Cloud CPA, September 5, 2026. https://bluecloudcpa.com/guides/small-business-business-use-of-home-irc-280a

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