How to use the home office deduction calculator
This calculator works out both IRS methods side by side and shows the larger one. You need three things: the size of your office, the size of your home, and your annual home costs.
- Choose own or rent. Homeowners deduct a share of mortgage interest, property tax and depreciation; renters deduct a share of rent.
- Enter square footage. Your office area divided by your home’s total area is your business-use percentage — the share of each home expense you can deduct under the regular method.
- Enter your net business profit before the home office. The deduction can’t be bigger than this (more on that below), and it drives the tax-savings estimate.
- Add annual expenses for the whole home. The calculator applies your percentage automatically. Costs that only affect the office, such as painting it, go in “direct office expenses” and count in full.
The results panel shows each method, the winner, a line-by-line Form 8829-style breakdown and an estimate of how much federal income tax and self-employment tax the deduction saves.
Who can take the home office deduction?
The deduction is for people who are self-employed — sole proprietors, freelancers, independent contractors, single-member LLC owners and partners — plus some statutory employees. To qualify, the space must be used:
- Regularly and exclusively for business. A desk in the corner of the guest room counts only if that defined area is never used for anything personal. (Daycare providers and inventory storage are exceptions to the exclusive-use rule.)
- As your principal place of business, or as a place where you regularly meet clients, or as a separate structure (such as a detached studio) used for the business. Doing your admin and management work at home counts even if you perform services elsewhere.
W-2 employees can’t deduct a home office for their employer’s work, even if they work remotely full time. Unreimbursed employee expenses were suspended from 2018 and the One Big Beautiful Bill Act made that permanent. If you have both a job and a side business, only the side business can use the deduction.
The simplified method: $5 per square foot
The simplified method lets you deduct $5 for each square foot of qualifying office space, up to 300 square feet — a maximum of $1,500 a year. There’s no Form 8829, no receipts for home costs and no depreciation to track or recapture when you sell.
The trade-offs: you can’t deduct actual expenses above that cap, you can’t carry unused amounts to next year, and the deduction still can’t exceed your business’s gross income limit. Homeowners using it keep deducting mortgage interest and property tax in full on Schedule A if they itemize.
The regular method (actual expenses, Form 8829)
The regular method deducts the business share of what it actually costs to run your home:
Regular deduction = business-use % × (rent or mortgage interest + property tax + insurance + utilities + repairs + HOA)
+ direct office expenses + depreciation
Depreciation = (home basis − land value) × business-use % ÷ 39
Depreciation is the piece most people forget. Because a home office is treated as nonresidential real property, the business share of the building (never the land) is depreciated straight-line over 39 years, using the mid-month convention in the first year. The basis is the lower of what you paid (plus improvements) or the home’s fair market value when you started using the office. Depreciation lowers your basis, and when you sell, the depreciation claimed after May 6, 1997 is taxed at up to 25% (“unrecaptured Section 1250 gain”) even if the rest of the gain is excluded.
Mortgage principal, the cost of lawn care and expenses for rooms you don’t use for business are never deductible.
Worked example: simplified vs regular
A single freelancer owns a 2,000 sq ft home and uses a 200 sq ft spare bedroom exclusively as an office — a 10% business-use percentage. Their 2026 net business profit is $60,000.
| Expense | Whole home | Business share |
|---|---|---|
| Mortgage interest | $12,000 | $1,200 |
| Real estate taxes | $4,000 | $400 |
| Insurance | $1,500 | $150 |
| Utilities | $3,600 | $360 |
| Repairs | $1,000 | $100 |
| Depreciation ($280,000 building × 10% ÷ 39) | — | $718 |
| Regular method | $2,928 | |
| Simplified method (200 sq ft × $5) | $1,000 |
The regular method is worth $1,928 more. Because a home office deduction lowers both self-employment tax and income tax, it saves this freelancer roughly $675 in federal tax with the regular method versus about $231 with the simplified method. (Under the regular method, the $1,600 of business-share interest and taxes moves from Schedule A to Schedule C, which matters only if you itemize.)
Which method should you choose?
| Simplified method | Regular method | |
|---|---|---|
| Deduction | $5/sq ft, max $1,500 | Actual expenses × business-use %, no cap |
| Record keeping | Square footage and proof of exclusive use | Receipts for every home expense, basis records |
| Depreciation | None (zero depreciation for those years) | 39-year straight line; recaptured on sale |
| Over the income limit | Lost — no carryover | Excess carries forward to future years |
| Form | Schedule C line 30 worksheet | Form 8829 |
| Usually better for | Renters with low rent, small offices, people who want simplicity | Larger offices, high-cost homes, high rent |
You can switch methods from year to year. If you go back to the regular method after using the simplified method, you use the optional depreciation tables for the remaining recovery period.
The gross-income limitation and carryovers
A home office can’t create or increase a business loss. Under the regular method, Form 8829 applies the deduction in three tiers:
- Mortgage interest and real estate taxes (business share) — always allowed, because you could deduct them anyway.
- Operating expenses — rent, insurance, utilities, repairs and HOA fees — allowed up to the profit that remains.
- Depreciation — allowed last, up to any profit still left.
Anything disallowed in tiers 2 and 3 carries forward to next year’s Form 8829. The calculator applies this order automatically and shows any carryover. Under the simplified method, the amount over the limit is simply lost.
Tips to get the deduction right
- Measure and photograph the space so you can prove exclusive use if asked.
- Separate direct and indirect costs. Painting your office is 100% deductible; painting the whole house is indirect.
- Don’t double-count. If you deduct your internet as a business expense elsewhere, leave it out of utilities here.
- Remember the rest of your write-offs. Office furniture and computers are deducted separately, often in full the first year — see the depreciation calculator. Driving from a qualifying home office to clients is deductible business mileage, not commuting — see the mileage deduction calculator.
- See the whole picture. Plug your deduction into the 1099 tax calculator or self-employment tax calculator to update your quarterly estimated payments. New to 1099 work? Read Got a 1099? Here’s exactly what to do next.
Frequently asked questions
How much can I deduct for a home office?
With the simplified method, $5 per square foot up to 300 sq ft — a maximum of $1,500. With the regular method there’s no fixed cap: you deduct your business-use percentage of rent or mortgage interest, property tax, insurance, utilities, repairs and depreciation, limited to your business profit. In our example, a 200 sq ft office in a 2,000 sq ft home produces $2,928 under the regular method.
Is the regular or simplified home office method better?
The regular method usually wins for larger offices, homeowners with high interest and property taxes, and renters in expensive areas. The simplified method wins when your office is small, your housing costs are low or you value simplicity and want to avoid depreciation recapture. The calculator compares both instantly.
Can W-2 employees take the home office deduction?
No. Employees who work from home for an employer can’t deduct a home office on their federal return. The deduction is for self-employed people, partners and certain statutory employees. Some states still allow unreimbursed employee expenses.
Do I have to pay back home office depreciation when I sell?
Depreciation you claimed (or could have claimed) after May 6, 1997 is taxed as unrecaptured Section 1250 gain at a maximum 25% rate when you sell, even if the rest of your gain is excluded under the $250,000/$500,000 home sale exclusion. The simplified method avoids this because it has no depreciation.
Can I deduct a home office if I rent?
Yes. Renters multiply annual rent (plus renters insurance, utilities and repairs they pay) by the business-use percentage. Rent is often the largest single home office expense, so renters in high-cost cities frequently get far more from the regular method than the $1,500 simplified cap.
What if my home office deduction is more than my business income?
The deduction can’t create a loss. Under the regular method, mortgage interest and property tax are allowed in full, but excess operating expenses and depreciation carry forward to next year. Under the simplified method, the excess is lost.
Does a home office have to be a separate room?
No. A clearly defined area of a room qualifies if it’s used regularly and only for business. Measure just that area. A dining table you also eat at doesn’t qualify.