S-Corp Owners: Reimburse 2026 Mileage by Dec 31

You elected S-corp status a year or two ago, maybe as a real estate agent, consultant, contractor or photographer, because your accountant said it would save self-employment tax. You still drive your own car to clients and job sites. Now it is late October and your CPA's year-end email asks the question you have been avoiding: “Has the company reimbursed you for your 2026 mileage yet?” It hasn't. You assumed you'd just deduct the miles at tax time, like you did on Schedule C.

Who this is for: owners who work in their own S corporation (including an LLC that elected S status on Form 2553) and drive a personal car for the business. C-corporation owner-employees are in the same position and can use the same reimbursement mechanics. Who it is not for: sole proprietors and single-member LLCs that never made the election. You deduct business miles directly on Schedule C, and the Schedule C car-expenses guide covers that. Partners in a multi-member LLC follow partnership rules instead. If the company owns the car, there is nothing to reimburse. Personal use of a company car is a separate fringe-benefit question for your payroll provider.

Why the Schedule C habit stops working

The IRS treats a shareholder who performs services for an S corporation as an employee, and the corporation pays them wages (IRS: S corporation employees, shareholders and corporate officers). An employee's unreimbursed business expenses are a miscellaneous itemized deduction, and section 67(h) of the tax code disallows those. The 2017 law suspended them through 2025. The One Big Beautiful Bill Act of July 2025 made the disallowance permanent from 2026, with a carve-out only for eligible educators. So miles you drove for your S corp but never got paid back for give you no federal deduction anywhere. You have no Schedule C to put them on, and your personal return can't take them.

Reimbursement flips that. Under an accountable plan the payment isn't wages: it stays off your W-2, with no income tax and no payroll tax (Treas. Reg. §1.62-2(c)). The corporation deducts it as an ordinary business expense, which lowers the income that flows to your K-1.

What makes it an accountable plan

The regulation has three requirements, and all three have to hold:

• Business connection. The company pays only for business expenses you incurred as its employee. Business miles qualify. Commuting miles do not, and that includes the drive from home to a regular office.
• Substantiation. You account for each expense to the company within a reasonable period. For car use, that means the details section 274(d) requires.
• Return of excess. If you were advanced more than you substantiate, you must pay the difference back within a reasonable period.

For mileage, Rev. Proc. 2019-46 makes the substantiation part simple. If the company pays a cents-per-mile allowance no higher than the IRS business standard mileage rate, the amount is deemed substantiated. You still have to give the company the time, place and business purpose of each trip (Rev. Proc. 2019-46, sections 7.01–7.02). That's your mileage log: date, where you went, why, and how far. Unlike the FAVR method, the plain cents-per-mile allowance isn't barred for owners or other “control employees”. The cap is the rate itself. Anything paid above it counts as wages.

Worked example: one owner, one catch-up reimbursement

Dana runs a one-person design consultancy taxed as an S corp. She meets clients, visits print shops and drives to job sites in her own SUV. Her log shows 4,200 business miles from January to June and 3,600 from July 1 to November 30. She expects about 600 more in December.

The $6,237 is not on Dana's W-2, and the S corp deducts it, so her K-1 income drops by the same amount. At a 22% bracket that is roughly $1,100–$1,370 less federal income tax, depending on how the 20% qualified business income deduction applies to her, plus any state tax. If the company never pays her back, the same miles are worth $0 on her return.

The honest catch: January miles reported in November

The regulation says a “reasonable period” depends on the facts and circumstances. It also gives a safe harbor: expenses substantiated within 60 days after you incur them, and any excess returned within 120 days, are automatically reasonable (§1.62-2(g)(2)). Dana's February miles, turned in this November, are well outside that window.

That doesn't automatically disqualify them, but it does make them a judgment call. If the IRS decided the arrangement didn't meet the accountable-plan rules, the payment would be treated as wages. It would then be taxable to her and subject to payroll tax, which is the opposite of what she wanted. Give your CPA the dated log for the whole year and let them decide how much of the catch-up to run through the plan. Then do it properly from here on.

Your year-end checklist

1. Put the plan in writing now if you don't have one. A one-page policy or corporate resolution says the company reimburses business miles at no more than the IRS standard rate, requires a log within 60 days, and requires any excess advance to be returned. The regulation tests how the arrangement works rather than requiring a document, but a written plan adopted before you pay yourself is the easiest proof that it exists.
2. Get the 2026 log in order. For every business trip, record the date, start and end points, business purpose and miles. If months are missing, rebuild them from calendars and invoices, and mark them as reconstructed.
3. Split the miles at July 1 and price each half at its own rate.
4. Pay it from the business account and book it as a car or travel expense reimbursement, not as a distribution or as payroll. Keep the log with the payment record.
5. Pay December by December 31 if you want the deduction in 2026. A cash-basis business deducts expenses in the year it pays them (IRS Publication 538). A January check is still fine for you, but it becomes a 2027 deduction for the company.
6. Switch to monthly in 2027. Submit last month's log in the first week of each month and the company pays it. That keeps every trip inside the 60-day safe harbor.

Where TaxMiles fits, and where it doesn't

TaxMiles is the log, not the plan. It doesn't know you're an S corp, doesn't write an accountable-plan resolution, doesn't run payroll and can't pay you. Your accountant and your business bank account handle those parts.

The log is the part that usually breaks, and that's what the app does. It records drives automatically on your iPhone. You mark each one business or personal and add the purpose. In the report you pick a range, such as Last Month, Last Quarter or custom dates, and see the trips, the miles and the dollar amount at the IRS rate for each trip's date. A 2026 report splits at 72.5¢ and 76¢ by itself. The PDF log lists date, from, to, purpose, category, miles and amount on every row, which is what you attach to each reimbursement. It can't recover trips from before you installed it, so earlier months still have to be rebuilt by hand.

The free plan covers your first 40 business trips in total, not per month. Exporting the PDF or CSV log is a TaxMiles Pro feature, at $7.99 a month or $59.99 a year.

Frequently asked questions

Can I deduct my car mileage on my own return if I own an S corporation?

Generally no. If you work in your S corporation you are its employee, and unreimbursed employee business expenses are a miscellaneous itemized deduction that section 67(h) of the tax code disallows. The One Big Beautiful Bill Act made that permanent from 2026, with an exception for eligible educators only. The way to get the benefit is for the corporation to reimburse you under an accountable plan and deduct the reimbursement itself.

How much per mile can my S corporation reimburse me tax-free in 2026?

Up to the IRS business standard mileage rate in force on the date of each trip: 72.5 cents a mile for January 1 to June 30, 2026 and 76 cents a mile for July 1 to December 31, 2026. Under Rev. Proc. 2019-46 that amount is deemed substantiated as long as you give the company the date, place and business purpose of each trip. Anything paid above the rate is treated as wages.

Do I need a written accountable plan?

The regulation, Treas. Reg. 1.62-2, tests how the arrangement actually works: business connection, substantiation within a reasonable period, and return of any excess. It does not prescribe a document. A short written policy or corporate resolution adopted before the first reimbursement is still the easiest way to prove the plan exists, and most tax professionals will ask for one.

What if the company reimburses my December miles in January 2027?

That can still be tax-free to you if you substantiate the miles within a reasonable period, and 60 days is a safe harbor. But a cash-basis corporation deducts an expense in the year it pays it, so a January payment is a 2027 deduction for the company, not a 2026 one. If you want the deduction on the 2026 return, pay by December 31.

I have a single-member LLC. Does this apply to me?

Only if the LLC elected to be taxed as an S corporation (Form 2553). A single-member LLC that never made the election is a disregarded entity: you report the business on Schedule C and deduct business miles there directly, with no reimbursement needed.

Related reading: what the IRS requires in a mileage log; W-2 employee mileage by state, since some states still allow what the federal return doesn't; and the 2026 mileage calculator, which splits miles at July 1.

Sources: Treas. Reg. §1.62-2 (accountable-plan requirements; nonaccountable payments are wages; reasonable period and the 60/120-day fixed-date safe harbor); IRS Rev. Proc. 2019-46 (mileage allowance up to the business standard rate deemed substantiated when time, place and business purpose are substantiated; FAVR not available to control employees); 26 U.S.C. §67(h) (miscellaneous itemized deductions disallowed for tax years after 2017; numbered §67(g) before Pub. L. 119-21, the One Big Beautiful Bill Act, redesignated it and removed the 2025 end date); IRS S corporation employees, shareholders and corporate officers (shareholder-officers who perform services are employees); IRS Publication 463, chapter 6 (reimbursements and accountable plans); IRS Publication 538 (cash method: deduct expenses in the year paid); IRS standard mileage rates (72.5¢ January 1–June 30 and 76¢ July 1–December 31, 2026; IR-2026-29). Checked October 18, 2026.

This article is general information for US taxpayers, not tax, legal or accounting advice. The worked example is simplified: one owner, one bracket, no state tax and no credits. Whether a catch-up reimbursement fits your plan depends on your facts, so ask the tax professional who prepares your 1120-S. TaxMiles is published by Gigabyte LLC, the company that wrote this page, and is not affiliated with the IRS. Phone Diet, RecipeScan and Trending Music below are also our apps. Apple and iPhone are trademarks of Apple Inc., which doesn’t endorse this article.