Home Office Deduction

Overview

Calculates the home office deduction (Form 8829 or simplified method) for self-employed individuals who use part of their home regularly and exclusively for business. Two methods are available: the simplified method ($5 per square foot) and the actual expense method (percentage of real housing costs).

Wilson Tools Used

• transaction_search — Find mortgage/rent, utilities, insurance, and repair transactions
• spending_summary — Summarize housing-related expenses for the tax year
• export_transactions — Export housing expenses for Form 8829 or CPA review

Workflow

1. Confirm the home office qualifies: the space must be used regularly and exclusively for business.
2. Ask for the square footage of the office and the total square footage of the home.
3. Calculate the business-use percentage: office_sq_ft / total_home_sq_ft.
4. Choose a method:

Method 1: Simplified

• Multiply office square footage by $5/sq ft.
• Maximum: 300 sq ft = $1,500 max deduction.
• No depreciation, no Form 8829 required.
• Enter on Schedule C, Line 30.

Method 2: Actual Expenses (Form 8829)

1. Use transaction_search to find these expense categories:

• Mortgage interest or rent
• Property taxes
• Homeowners/renters insurance
• Utilities (electric, gas, water, internet, phone)
• Repairs and maintenance
• Depreciation of the home (residential, 27.5-year MACRS for the business-use portion)

1. Use spending_summary to total each category for the tax year.
2. Multiply each total by the business-use percentage.
3. Sum all adjusted amounts. This is the actual expense deduction.
4. Compare to the simplified method result and use whichever is larger.

Comparison

Without Wilson

1. Measure your office space in square feet.
2. Simplified method: Multiply sq ft (max 300) by $5. That is your deduction.
3. Actual expense method:

• Gather 12 months of mortgage/rent statements, utility bills, insurance declarations, and repair receipts.
• Sum each category for the year.
• Calculate business-use percentage: office sq ft / total home sq ft.
• Multiply each expense category total by the business-use percentage.
• Add all adjusted amounts together.
• Fill out Form 8829 and attach to your Schedule C.

1. Compare both methods and use the higher deduction (you can switch methods year to year).

Important Notes

• "Regular and exclusive use" is strictly enforced. A guest bedroom with a desk in the corner does not qualify unless the desk area is used only for business.
• Employees working from home generally cannot claim this deduction (eliminated for W-2 employees under the Tax Cuts and Jobs Act through 2025). Only self-employed individuals qualify.
• If you use actual expenses and claim depreciation on your home, you may owe depreciation recapture tax when you sell.
• The deduction cannot create a business loss. Any excess carries forward to next year.
• If you rent, use your rent payment instead of mortgage interest and property taxes.
• This is not tax advice. Consult a CPA or tax professional for filing decisions.