S Corp Home Office Reimbursement: The Accountable Plan That Replaced the Deduction You Lost.

A consultant runs her practice from a spare bedroom, deducts the office on Form 8829 every spring, and eventually makes the S corp election because the self-employment tax math finally justifies it. The next April her home office deduction is simply gone. Form 8829 belongs to Schedule C, and she no longer files one. She is now an employee of her own corporation, and employees have not been able to deduct a home office since 2018. The replacement is an S corp home office reimbursement through an accountable plan, and done correctly it beats the deduction it replaced: the corporation deducts the money, you receive it tax-free, and none of it runs through payroll.

An accountable plan is not something you file or elect. It is any reimbursement arrangement that meets the three tests of Treas. Reg. §1.62-2: a business connection under paragraph (d), substantiation under paragraph (e), and the return of any excess payments under paragraph (f). The business connection test means the expense would have been deductible under §162 if the corporation had paid it directly. For a home office, that routes you through IRC §280A(c)(1): the space must be used regularly and exclusively as the principal place of business, and because you are an employee, the use must be for the convenience of the employer. When the corporation has no other office, that last test is comfortably met.

The execution is a paper trail, and the paper is what survives an exam. Put the plan in writing and adopt it by corporate resolution, even if you are the only director. Then submit an expense worksheet on a regular cadence, monthly or quarterly, listing the actual home costs for the period and the business-use percentage, and have the corporation pay it by check or transfer. The regulation defines a reasonable period with a fixed-date safe harbor in §1.62-2(g)(2)(i): an advance made within 30 days of the expense, substantiation within 60 days after the expense is paid or incurred, and any excess returned within 120 days all count as reasonable. Miss the three tests and §1.62-2(c)(5) recharacterizes every dollar as paid under a nonaccountable plan, which means W-2 wages subject to income tax and both halves of payroll tax.

Before 2018, an owner who paid home office costs personally could at least deduct them as unreimbursed employee expenses, a miscellaneous itemized deduction subject to the 2% floor. The Tax Cuts and Jobs Act added §67(g) and suspended those deductions for 2018 through 2025, and the One Big Beautiful Bill Act made the suspension permanent in July 2025. There is no personal deduction left to claim, which is why the reimbursement is not a nicety but the entire strategy. The other tempting shortcut, dropping a share of your utilities and insurance directly on the 1120-S as corporate expenses, fails because the corporation did not incur them. You did. The accountable plan is the bridge that moves your personal outlay onto the corporate return legitimately.

The most common wrong answer is rent. The corporation signs a lease for your spare bedroom at $1,000 a month, deducts $12,000, and you plan to offset the rental income with a share of your home expenses. IRC §280A(c)(6) kills the offset. When an employee rents any part of their home to their employer while performing services as an employee, the statute denies every deduction attributable to that rental other than the mortgage interest and property taxes you could deduct anyway. You pick up $12,000 of taxable income with nothing against it. Do not confuse this with the Augusta rule, which lives in §280A(g) and excludes rent for 14 or fewer days per year, or with the self-rental rule, which governs a separate commercial building you lease to the company. A flat monthly stipend is the other wrong door: $500 a month with no worksheet and no receipts fails the substantiation test and lands on your W-2.

The reimbursement is the business-use percentage, usually office square footage over total square footage, applied to actual costs: utilities, homeowners or renters insurance, repairs and maintenance that benefit the whole home, HOA dues, pest control, security monitoring, and a defensible share of internet. Renters include the rent itself, which often makes the numbers better than a homeowner's. Mortgage interest and property taxes can go in pro rata, but the reimbursed slice cannot also be itemized on Schedule A. Depreciation is the judgment call. Reimbursing it is defensible, but gain attributable to depreciation after May 6, 1997 is carved out of the §121 home-sale exclusion by §121(d)(6), so the cautious route sticks to operating costs and skips it.

One method is off the table. The $5 per square foot simplified method of Rev. Proc. 2013-13 computes a deduction on an individual return, capped at 300 square feet. An accountable plan reimburses substantiated actual expenses under §1.62-2(e), and a per-foot allowance backed by no records is just an allowance, taxable as wages. Keep the worksheet, keep the utility bills, and the reimbursement holds.

Qualifying the office as your principal place of business carries a quiet bonus. Under Rev. Rul. 99-7, when your home is your principal place of business under §280A(c)(1)(A), driving from home to any other work location in the same business is deductible transportation, not commuting. The corporation can reimburse those miles through the same accountable plan at the standard mileage rate, 72.5 cents per mile for 2026 under Notice 2026-10. For an owner who regularly drives to client sites, the mileage reimbursement frequently outgrows the home office numbers that unlocked it.