Simplified vs. Regular: Which Home Office Deduction Method Actually Saves You More?

Most self-employed people pick the simplified home office method because it is easy. It is $5 per square foot, no receipts, no extra form. Done in thirty seconds.

It is also, for most people, the smaller number.

The regular method takes a percentage of what your home actually costs to run. If your home costs more than $5 per square foot per year to keep, and almost every home in America does, the regular method wins. Sometimes by a few hundred dollars. Often by a few thousand.

Here is how to tell which method is bigger for you, without doing both by hand.

The one number that decides it

Both methods multiply your office space by a rate.

The simplified method uses a fixed rate: $5 per square foot, capped at 300 square feet, for a maximum deduction of $1,500.

The regular method uses your own rate: total annual home costs divided by total square footage.

That means the comparison collapses to a single question.

Divide everything you spend on your home in a year by your home's total square footage. If that number is more than $5, the regular method gives you a bigger deduction.

Count rent or mortgage interest, property tax, utilities, homeowners or renters insurance, and whole-home repairs and maintenance. A 900 square foot apartment at $2,200 a month is already $29 per square foot before the electric bill. A paid-off 2,500 square foot house with low utilities might land at $4. Those are the two ends of the range, and almost everyone reading this is closer to the first one.

What each method actually is

Simplified method. $5 per square foot of space used regularly and exclusively for business, up to 300 square feet. Maximum deduction $1,500. No depreciation, and no depreciation recapture later when you sell. Mortgage interest and property taxes stay on Schedule A in full if you itemize. If the deduction exceeds your business income, the excess is gone. There is no carryover.

Regular method. Your business-use percentage applied to your actual home expenses, reported on Form 8829. Business-use percentage is office square footage divided by total home square footage. You include rent or mortgage interest, property tax, insurance, utilities, and general repairs at that percentage, plus 100 percent of expenses that apply only to the office itself, like painting that room. Homeowners also claim depreciation. Anything you cannot use this year because business income was too low carries forward to future years.

Both methods require the same thing to qualify: regular and exclusive use of the space, and it has to be your principal place of business. The method you choose does not change who is eligible. It only changes the size of the number. Our complete guide to the home office deduction walks through the eligibility tests in detail.

Example one: the renter

Priya is a fractional CMO. She rents a 900 square foot apartment and works from a 120 square foot second bedroom that holds a desk, a monitor, and nothing else.

Her business-use percentage is 120 divided by 900, or 13.3 percent.

Her annual home costs:

Simplified: 120 sq ft x $5 = $600

Regular: $28,420 x 13.3% = $3,789

The regular method is $3,189 bigger. For someone in the 22 percent bracket, that extra deduction is worth roughly $1,100 in combined federal tax, because a Schedule C deduction cuts both income tax and self-employment tax. State tax savings would come on top of that.

Priya's home costs $31.58 per square foot per year. The simplified method was never going to compete.

Example two: the homeowner

Marcus is an independent consultant. He owns a 2,000 square foot house and uses a 200 square foot room as his office.

Business-use percentage: 10 percent.

Simplified: 200 sq ft x $5 = $1,000

The regular method is $2,887 bigger, worth close to $1,000 in combined federal tax at the same bracket.

One honest caveat for homeowners: if you itemize, your mortgage interest and property tax are already deductible on Schedule A. Moving 10 percent of them to Form 8829 does not create new income tax savings on that portion, though it does shelter it from self-employment tax. The genuinely new money is in the insurance, utilities, repairs, and depreciation. If you take the standard deduction, which most people do, the full gap is real. This is exactly the kind of thing worth running both ways instead of guessing.

When the simplified method is the right call

It is not always the loser. Choose it when:

• Your home is cheap per square foot. A paid-off house in a low-cost area with modest utilities can land under $5. Do the division before you assume.
• You do not have the records. The regular method needs twelve months of expense documentation. If your first year of receipts is a shoebox, take the $5 and build a better system for next year.
• You plan to sell soon and want to avoid depreciation recapture. Depreciation you claim on a home office gets recaptured as unrecaptured Section 1250 gain when you sell, taxed at up to 25 percent. Years you use the simplified method generate no depreciation and no recapture.
• Your business had a very small profit. Both methods are capped at your business income. The difference is that the regular method lets you carry the unused portion forward. The simplified method does not.

And one case where the regular method almost always wins by a wide margin: an office larger than 300 square feet. The simplified method stops counting at 300. The regular method does not.

You can switch every year

This is the part people get wrong. The choice is not permanent. You can use the simplified method one year and the regular method the next, and switch back the year after. The only restriction is that once you have filed for a given year, you cannot amend to change methods for that same year.

So the right habit is not to pick a method. It is to run both, every year, and take the bigger one. Your rent goes up, you move, you finish a basement, your utilities spike. The answer changes.

How Sumly fits in

We built the home office feature in Sumly to do exactly this comparison, because doing it by hand is why most people default to the $5 and move on.

You enter your office square footage and your home's total square footage once. Sumly pulls the home expenses already flowing through your connected accounts, calculates your business-use percentage, and shows you both numbers side by side: what the simplified method gives you, what the regular method gives you, and the difference in actual tax dollars. If you are a homeowner, it handles the depreciation piece too.

You see which method wins before you file, not after. And because Sumly is categorizing your expenses all year, the documentation the regular method requires is already there instead of being something you reconstruct in April.

Sumly does not invent deductions. It does not decide that your kitchen table is an office. It runs the math the IRS rules allow on the numbers you actually have, and our licensed tax professionals stand behind the filing.

Sign up free and see which method you should be using.

Related reading

• The Home Office Deduction for the Self-Employed: A Complete Guide
• Myth-Buster: Does Writing Something Off Mean It's Free?
• Mileage Deduction for the Self-Employed
• Taxes and Bookkeeping for Fractional CFOs and Fractional Executives

Frequently asked questions

Which home office method gives the bigger deduction? Usually the regular method. Divide your total annual home costs by your home's total square footage. If the result is more than $5, the regular method produces a larger deduction than the simplified method's $5 per square foot.

What is the maximum home office deduction under the simplified method? $1,500. The simplified method allows $5 per square foot for up to 300 square feet, and 300 x $5 is $1,500. The regular method has no square footage cap.

Can I switch between the simplified and regular methods? Yes. You choose year by year. You cannot change methods for a year after you have filed that year's return, but nothing stops you from using the simplified method in 2025 and the regular method in 2026.

Does the regular method increase my audit risk? No. A correctly calculated home office deduction is a normal business deduction. What creates problems is claiming space that is not used regularly and exclusively for business, or claiming a percentage you cannot support with square footage and expense records.

Do renters do better with the regular method than homeowners? Often, yes. Rent is fully includable at your business-use percentage, and rent per square foot is high in most markets. Homeowners deduct mortgage interest rather than the full mortgage payment, which is a smaller base, though depreciation adds to it.

What is depreciation recapture on a home office? If you claim depreciation on your home office under the regular method, that depreciation is recaptured when you sell the home and taxed as unrecaptured Section 1250 gain, at a rate up to 25 percent. It is a timing tradeoff, not a penalty, and it does not apply to years you used the simplified method.

Does the home office deduction reduce self-employment tax? Yes. It is a Schedule C business deduction, so it lowers both your income tax and your self-employment tax. That is why the combined value of the deduction is larger than your income tax bracket alone would suggest.