S Corp Vehicle Deduction: Ownership, Depreciation, and Reimbursement

An S Corp vehicle deduction works one of two ways: the corporation owns the vehicle and deducts actual operating costs and depreciation directly on Form 1120-S, or the shareholder-employee owns the vehicle personally and the S Corp reimburses business use through a formal accountable plan. Which path you’re on determines every other rule that follows. For 2026, the business standard mileage rate is 72.5 cents per mile, and the One Big Beautiful Bill Act permanently restored 100 percent bonus depreciation for qualifying property acquired after January 19, 2025.¹

Who Owns the Vehicle Decides Everything

When the S Corporation holds the title, it claims deductible operating expenses directly and reports the vehicle as listed property on Form 4562.² Fuel, insurance, maintenance, and depreciation are deductible, but only to the extent of business use. Any personal use by the shareholder-employee becomes a taxable fringe benefit on their W-2.

When the shareholder-employee owns the vehicle, the S Corp cannot put those expenses on its own return at all. Instead, the corporation reimburses the employee under an accountable plan. Done correctly, the reimbursement is deductible for the S Corp and tax-free to the employee. Done incorrectly, every dollar becomes taxable wages subject to withholding and payroll taxes.

One rule catches many owners off guard: a corporation cannot use the standard mileage rate on a company-owned vehicle. That rate is available for employee reimbursements, not for computing the corporation’s own deduction. If the S Corp holds the title, you are on the actual expense method.

Actual Expenses on a Company-Owned Vehicle

Every deductible cost has to be tracked and multiplied by the business use percentage. Deductible expenses include fuel, oil changes, tires, repairs, insurance premiums, registration fees, loan interest, and depreciation. The math is unforgiving. If the vehicle is driven 20,000 miles in a year and 15,000 of those are for business, business use is 75 percent, and only 75 percent of each expense is deductible. The IRS expects that percentage to be supported by a contemporaneous mileage log, not reconstructed at tax time.

Depreciation Rules for 2026

Depreciation is usually the largest piece of a company-owned vehicle deduction, and the 2026 rules are more generous than they’ve been in years. The One Big Beautiful Bill Act permanently restored 100 percent bonus depreciation for qualifying property acquired after January 19, 2025, reversing the phase-down that would have cut the allowance to 20 percent for 2026 under prior law.³ How much that actually saves depends on the type of vehicle.

Passenger Vehicles Under 6,000 Pounds

Passenger cars, small crossovers, and light trucks under 6,000 pounds GVWR are subject to annual depreciation caps regardless of how much bonus depreciation is theoretically available. For vehicles placed in service in 2026, the maximum first-year depreciation deduction is $20,300 when bonus depreciation applies, or $12,300 without it.⁴ The caps for later years:

Year 2: $19,800
Year 3: $11,900
Year 4 and beyond: $7,160 per year until the cost is fully recovered

The caps apply per vehicle and are reduced proportionally for personal use. On a $50,000 sedan used 80 percent for business, the first-year deduction maxes out at $16,240 (80 percent of $20,300), not the full $20,300.⁵

Heavy Vehicles Over 6,000 Pounds

This is where the real savings live. Trucks, vans, and SUVs with a gross vehicle weight rating over 6,000 pounds are exempt from the luxury auto caps, so bonus depreciation and Section 179 apply without those annual limits. For 2026, the overall Section 179 expense limit is $2,560,000, with a phase-out beginning at $4,090,000 of total qualifying property placed in service.⁶

Within the heavy category, heavy SUVs face a separate Section 179 cap of $32,000, but they can still claim 100 percent bonus depreciation on the remaining cost.⁶ Pickup trucks with beds at least six feet long and cargo vans aren’t subject to that SUV cap and can potentially be written off entirely in year one through Section 179.

A practical example: an S Corp buys a qualifying heavy SUV for $70,000 in 2026 at 100 percent business use. It takes $32,000 under Section 179 and applies 100 percent bonus depreciation to the remaining $38,000, deducting the full $70,000 in year one. The same $70,000 spent on a passenger sedan would be capped at $20,300 that year.

The 50 Percent Business Use Threshold

If business use of a listed property vehicle drops to 50 percent or below in any year, the S Corp loses access to Section 179, bonus depreciation, and accelerated MACRS depreciation for that vehicle. The corporation must switch to the alternative depreciation system, which uses straight-line depreciation over a longer recovery period.⁵

It gets worse. If the vehicle was used more than 50 percent for business in earlier years and claimed accelerated depreciation, then drops below the threshold later, the S Corp must recapture the difference between the accelerated depreciation already claimed and what would have been allowed under straight-line. That recaptured amount is added back to the corporation’s gross income.⁵ A large Section 179 deduction in year one followed by business use slipping in year two produces a painful bill.

Personal Use of a Company Vehicle Is Taxable

When the S Corp owns the vehicle and the shareholder-employee uses it for errands, commuting, or weekend trips, the personal use value is a taxable fringe benefit. The corporation calculates that value and reports it on the employee’s W-2 as additional compensation, subject to income tax withholding and payroll taxes. Skipping this step is a common audit trigger.

The IRS allows several methods to value personal use:⁷

General valuation rule, based on the fair market value of leasing a comparable vehicle on the same terms in your area. This is the default when no other method applies.
Cents-per-mile rule, using the standard mileage rate (72.5 cents for 2026) multiplied by personal miles. Available only if the vehicle’s value when first made available for personal use doesn’t exceed $61,700 in 2026.⁸
Annual lease value rule, using an IRS table based on the vehicle’s fair market value, then prorating for personal use percentage.
Commuting rule, valuing each one-way commute at $1.50. Available only when the employer requires the employee to commute in the vehicle and prohibits other personal use.

The only way to avoid reporting a fringe benefit is if the vehicle qualifies as a working condition fringe, meaning 100 percent business use with no personal use at all, or the vehicle is a qualified nonpersonal use vehicle like a clearly marked delivery truck that isn’t suitable for personal driving.

Which Miles Count as Business Travel

Not every drive between appointments is deductible. Driving from your home to your regular office or place of business is commuting, and commuting is never deductible regardless of distance or the calls you make on the way.⁹

The exception that matters most for S Corp owners: if you have a qualifying home office that serves as your principal place of business, every drive from your home office to any other work location in the same business counts as deductible business travel.⁹ Without that designation, a shareholder-employee who drives from home to a client site is racking up commuting miles. Setting up and legitimately using a home office can convert thousands of otherwise nondeductible miles into business travel.

Drives between two work locations during the business day always count as business miles, home office or not. Travel to a temporary work location outside your regular metropolitan area is also deductible, as long as the assignment is realistically expected to last one year or less.¹⁰

Reimbursing a Shareholder-Employee Through an Accountable Plan

When the shareholder-employee owns the vehicle personally, the accountable plan is the mechanism that lets the S Corp deduct reimbursements as a business expense while keeping them off the employee’s taxable income. The plan must be a written policy adopted by the corporation, and it must satisfy three requirements:¹¹

Business connection. The expense must be an ordinary and necessary cost incurred while performing services as an employee.
Substantiation. The employee must provide records documenting the amount, date, destination, and business purpose of each trip within a reasonable time.
Return of excess. Any reimbursement exceeding substantiated expenses must be returned to the corporation within a reasonable time.

The simplest reimbursement approach is the standard mileage rate: 72.5 cents per mile for 2026.¹ The employee submits a mileage log, the corporation reimburses at or below the IRS rate, and no receipts for individual fuel purchases or repairs are needed. Alternatively, the S Corp can reimburse the employee’s actual expenses proportional to business use, but that requires the employee to submit detailed receipts.

When the Plan Fails

If any of the three requirements isn’t met, the IRS reclassifies the whole arrangement as a non-accountable plan. Every dollar of reimbursement becomes taxable wages reported on the W-2, subject to income tax withholding, Social Security, and Medicare. The S Corp owes the employer share of payroll taxes on those amounts.

The most common failures are sloppy recordkeeping and paying a flat monthly car allowance with no substantiation. A flat monthly payment is never an accountable plan, whatever the corporation calls it. The IRS treats it as additional compensation from day one.

Why an Accountable Plan Is Now the Only Route

Before 2018, an employee who wasn’t reimbursed could deduct business vehicle expenses on their personal return as a miscellaneous itemized deduction. The Tax Cuts and Jobs Act eliminated that deduction, and the One Big Beautiful Bill Act made the elimination permanent.¹² A shareholder-employee who uses a personal vehicle for S Corp business without an accountable plan gets no deduction anywhere. The expense simply disappears for tax purposes.

Documentation the IRS Expects

Vehicles are listed property, which means the substantiation bar is higher than for most business assets. Section 274 requires adequate records showing four elements for each business trip: the amount, the time and place of travel, the business purpose, and the business relationship to the person visited or destination.¹³

A proper mileage log records starting and ending odometer readings for the year, plus the date, destination, business purpose, and miles driven for each individual trip. The purpose has to be specific. “Met with Jones Construction about roofing bid” passes; “business” does not. Entries should be made at or near the time of each trip. Logs reconstructed at year-end from calendar appointments routinely fail on audit.

For the actual expense method, keep receipts for every deductible cost: fuel, repairs, insurance, loan payments, registration. Document total miles for the year, both business and personal, to compute the business use percentage that goes on Form 4562.¹⁴ That percentage is applied to every expense and to depreciation.

Digital mileage tracking apps have largely replaced handwritten logs and work well as long as they capture all required elements. Keep the records at least three years after filing the return that claims the deduction, and longer if you’re carrying forward unrecovered basis on a luxury vehicle, because the IRS can examine the original placed-in-service records for the entire recovery period.

1
Internal Revenue Service. IRS Sets 2026 Business Standard Mileage Rate at 72.5 Cents per Mile, Up 2.5 Cents
2
Internal Revenue Service. Instructions for Form 1120-S
3
Internal Revenue Service. Treasury, IRS Issue Guidance on the Additional First Year Depreciation Deduction Amended as Part of the One Big Beautiful Bill
4
Internal Revenue Service. REV. PROC. 2026-15
5
Office of the Law Revision Counsel. 26 U.S.C. 280F – Limitation on Depreciation for Luxury Automobiles
6
Internal Revenue Service. Rev. Proc. 2025-32
7
Internal Revenue Service. Publication 15-B Employer’s Tax Guide to Fringe Benefits
8
Internal Revenue Service. The Standard Mileage Rates and Maximum Automobile Fair Market Values Have Been Updated for 2026
9
Internal Revenue Service. Publication 463 (2025), Travel, Gift, and Car Expenses
10
Internal Revenue Service. Revenue Ruling 99-7 – Daily Transportation Expenses
11
Internal Revenue Service. Revenue Ruling 2006-56 – Section 62(c)
12
Internal Revenue Service. One, Big, Beautiful Bill Provisions
13
Office of the Law Revision Counsel. 26 U.S.C. 274 – Disallowance of Certain Entertainment, Etc., Expenses
14
Internal Revenue Service. 2025 Instructions for Form 4562 – Depreciation and Amortization (Including Information on Listed Property)