What this line means
The total deduction you can claim for the business use of your home this year. This is the bottom line of Form 8829 — the number that transfers to Schedule C, line 30. It combines the business portion of your mortgage interest, real estate taxes, utilities, insurance, repairs, and depreciation, all limited by your tentative profit from line 8. If your expenses exceed your profit, only the amount up to your profit is allowed here, and the rest carries forward.
Does this apply to you?
- You completed all applicable sections of Form 8829 and need the final deduction amount
- You are ready to transfer the home office deduction to Schedule C
- You want to confirm how much of your home expenses are deductible this year after all limits are applied
Easy to overlook
This number reduces both income tax and self-employment tax The deduction on line 36 flows to Schedule C, line 30, which reduces your net business profit. A lower profit means less income tax and less self-employment tax (15.3% on the first $176,100 of net earnings for 2025). Filers who skip Form 8829 because the deduction seems small underestimate the compounding effect — a $3,000 deduction saves roughly $460 in self-employment tax alone, on top of the income tax savings. 1 IRS Form 8829 instructions — Line 36
Compare this to the simplified method every year The simplified method gives you $5 per square foot, up to 300 square feet, for a maximum $1,500 deduction. If your line 36 amount is less than what the simplified method would give you, switch methods. You can change methods from year to year without restriction. Run both calculations annually to ensure you take the larger deduction. 2 IRS Publication 587 — figuring the allowable deduction
Watch out for this
Forgetting to enter this number on Schedule C. Form 8829 calculates the deduction, but it does not automatically appear on your return. You must transfer the amount from line 36 here to Schedule C, line 30. If you complete Form 8829 but leave Schedule C line 30 blank, you did the work but get no benefit.
Footnotes
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IRS Form 8829 Instructions, Line 36. https://www.irs.gov/instructions/i8829 ↩
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IRS Publication 587, Business Use of Your Home, Simplified Method. https://www.irs.gov/pub/irs-pdf/p587.pdf ↩