The Home Office Deduction: Both Methods, and Which One Wins
In short
The simplified method gives $5 per square foot up to 300 square feet, capped at $1,500, with no record-keeping. The regular method deducts the business-use percentage of actual home costs and typically yields $2,000–$4,000 for a dedicated room, but requires documenting every expense.
The qualifying test comes first
Neither method is available unless the space passes two tests: regular use and exclusive use. Exclusive is the one that disqualifies most people. The space must be used only for business — a desk in the corner of a bedroom qualifies only for the area of the desk and its immediate working space, and a dining table used for work and dinner qualifies for nothing.
The space must also be your principal place of business, or a place where you regularly meet clients. For most freelancers who work from home full time this is straightforward. For someone who rents a coworking desk and occasionally works at home, it is not.
The two methods side by side
| Simplified | Regular | |
|---|---|---|
| Calculation | $5 per sq ft | Business % of actual home expenses |
| Maximum | 300 sq ft / $1,500 | No cap |
| Record-keeping | Square footage only | Every utility bill, repair, insurance premium |
| Depreciation | Not taken | Taken — and recaptured when you sell |
| Home mortgage interest | Still itemised in full on Schedule A | Split between Schedule A and the business % |
| Loss limitation | Cannot create a loss | Cannot create a loss; excess carries forward |
A worked comparison
A freelancer rents a two-bedroom flat of 1,100 square feet and uses one 150 square-foot bedroom exclusively as an office — 13.6% of the home.
| Expense | Annual | Business share (13.6%) |
|---|---|---|
| Rent | $24,000 | $3,264 |
| Electricity and gas | $1,800 | $245 |
| Internet | $720 | $98 |
| Renter's insurance | $300 | $41 |
| Regular method total | $3,648 | |
| Simplified method | 150 sq ft × $5 | $750 |
The regular method is worth nearly five times as much here, and the gap is driven almost entirely by rent. This is the general pattern: if you rent in an expensive city, the regular method wins decisively. If you own a home with a small mortgage in a cheap market, the simplified method often wins once you account for the time cost of substantiating everything.
What does not qualify
- Space used for both work and personal life, however briefly — the exclusivity test has no de minimis allowance.
- A home office maintained for convenience when your employer provides one. Employees cannot take this deduction at all under current law; it is available only to the self-employed.
- Costs of the first telephone line into the home, which are personal by statute regardless of business use.
- Lawn care and general landscaping, unless clients regularly visit.
- Space that creates a business loss — the deduction is limited to the gross income from the business and the excess carries forward.
Does claiming it trigger an audit?
This belief is persistent and largely outdated. The deduction was an audit flag decades ago when home offices were unusual; after a pandemic that moved a third of the workforce home, a freelancer claiming one is unremarkable. What does attract attention is a claim that is disproportionate to the income it supports — a $9,000 home office against $18,000 of revenue invites a question that a $3,600 claim against $80,000 does not.
Keep a floor plan with measurements, a photograph of the space, and the bills. That package answers the question in full if it is ever asked.
Frequently asked questions
Frequently Asked Questions
How much is the home office deduction worth?
Can I claim a home office if I rent?
Does the space have to be a separate room?
Does the home office deduction reduce self-employment tax?
Related
Sources
- IRS Revenue Procedure 2025-32 — 2026 inflation adjustments — tax brackets, standard deduction, QBI thresholds.
- IRS Schedule SE instructions — Self-employment tax: the 92.35% adjustment, the Social Security wage base, the Medicare surtax.
- IRS Form 1040-ES — Estimated tax deadlines and the safe-harbour rules used for the quarterly schedule.
- IRS Publication 334 — Tax guide for small business — deductible expenses and net profit.
- IRS Social Security wage base — The $184,500 Social Security cap applied for 2026.
How these numbers are produced
Calculations follow the order of operations on the IRS forms themselves: net profit, the 92.35% adjustment, self-employment tax, the 50% deduction against AGI, the standard deduction, the §199A QBI deduction with its phase-out, then the federal brackets. State tax is computed separately on state AGI less that state's own standard deduction, because no state allows the federal QBI deduction and almost none allow the federal standard deduction.
What it does not cover. The calculators model a single filer or a married couple filing jointly with self-employment income as the main source. They do not model local income taxes, W-2 wages held alongside freelance work, itemized deductions, the alternative minimum tax, or credits. Where a local income tax exists, it is described on that state's page.
Not advice. SelfTaxCalc produces estimates, not tax advice. No one here is a CPA, an enrolled agent or a tax attorney, and nothing on this site creates a professional relationship. Estimates are a starting point for planning and for a conversation with a professional — they are not a substitute for one.