Employer payments for business driving stay tax-free only when they run through what the IRS calls an accountable plan, using either the standard mileage rate or a fixed and variable rate (FAVR) allowance with proper recordkeeping. These tax-free vehicle reimbursement rules come from Internal Revenue Code Section 62(c), Treasury Regulation 1.62-2, and Revenue Procedure 2019-46. Notice 2011-72, which is often cited in this context, actually addresses employer-provided cell phones and states on its face that it does not apply to other fringe benefits.1Internal Revenue Service. Notice 2011-72 The vehicle rules are separate, and getting them right matters more than ever now that employees can no longer deduct what their employer fails to reimburse.
The Three Accountable Plan Requirements
Under Section 62(c) and Treasury Regulation 1.62-2, a reimbursement arrangement qualifies as an accountable plan only if it meets three conditions:2eCFR. 26 CFR 1.62-2 – Reimbursements and Other Expense Allowance Arrangements
- The expense has a business connection.
- The employee substantiates the expense to the employer.
- The employee returns any amount paid that exceeds the substantiated expenses.
Miss any one of the three and the entire payment becomes taxable wages, subject to income tax withholding, Social Security and Medicare taxes, and federal unemployment tax. There is no partial credit.
For vehicles specifically, the IRS accepts two methods of substantiation when combined with proper mileage records: the standard mileage rate and a FAVR allowance.3Internal Revenue Service. Publication 463 – Travel, Gift, and Car Expenses Either can produce tax-free reimbursements. They work very differently.
Deadlines for Substantiation and Returning Excess
The regulation doesn’t leave “reasonable period of time” to interpretation. Treasury Regulation 1.62-2(g)(2) gives employers two safe harbors:2eCFR. 26 CFR 1.62-2 – Reimbursements and Other Expense Allowance Arrangements
- Fixed-date method. The employee substantiates each expense within 60 days after paying or incurring it and returns any excess within 120 days.
- Periodic-statement method. The employer issues statements at least quarterly listing outstanding amounts, and the employee has 120 days from each statement to substantiate or return.
Pick one and apply it consistently. When an employee blows past the applicable deadline, the unsubstantiated or unreturned amount becomes taxable wages no later than the first payroll period after the deadline expires.
The Standard Mileage Rate
The simpler method uses a single per-mile figure set annually by the IRS. For 2026, that rate is 72.5 cents per mile for business driving.4Internal Revenue Service. IRS Sets 2026 Business Standard Mileage Rate at 72.5 Cents per Mile, Up 2.5 Cents The rate covers every operating cost bundled together: fuel, insurance, depreciation, maintenance, registration, and tires. It’s based on an annual third-party study of actual driving costs.5Internal Revenue Service. Notice 2026-10
For each business trip, the employee logs the date, destination, business purpose, and miles driven. The employer multiplies substantiated miles by the rate and pays. That’s the whole process. No gas receipts, no insurance declarations. If the employer chooses to pay above the standard rate, the excess is taxable.3Internal Revenue Service. Publication 463 – Travel, Gift, and Car Expenses
The standard rate works well for moderate drivers in areas with typical vehicle costs. It tends to under-reimburse employees driving expensive vehicles or working in high-cost regions, which is where FAVR comes in.
Fixed and Variable Rate (FAVR) Allowances
A FAVR plan reimburses based on the actual costs of owning and operating a vehicle in the employee’s specific geographic area. Revenue Procedure 2019-46 lays out the rules.6Internal Revenue Service. Rev. Proc. 2019-46 The allowance has two parts, both paid at least quarterly:
- Fixed payment. Covers ownership costs that don’t scale with mileage: depreciation or lease payments, insurance, registration, and personal property taxes.
- Variable payment. Covers operating costs that do scale with mileage: fuel, oil, tires, and routine maintenance.
The employee has to qualify. Participation requires at least 5,000 substantiated business miles per year, or 80 percent of the plan’s annual business mileage figure, whichever is greater. That threshold can be prorated by month for mid-year entries or exits.6Internal Revenue Service. Rev. Proc. 2019-46
The employee must own or lease the vehicle, and the vehicle’s original cost when new must be at least 90 percent of the “standard automobile cost” used to build the allowance. For 2026, the maximum standard automobile cost for FAVR purposes is $61,700.5Internal Revenue Service. Notice 2026-10 The vehicle can’t be older than the plan’s retention period allows.
On the employer side, FAVR is administratively heavier. The allowance must be built on current local cost data, both components paid at least quarterly, and each covered employee provided an annual statement within 30 days of the calendar year’s end. In practice, keeping the plan compliant means refreshing the underlying data each year. Employers who don’t want that workload usually stay with the standard mileage rate.
Business Miles vs. Commuting
This is where reimbursement plans most often go wrong. The IRS draws a hard line: driving between home and your regular workplace is commuting, and commuting is never reimbursable tax-free, no matter the distance and no matter whether you work during the drive.3Internal Revenue Service. Publication 463 – Travel, Gift, and Car Expenses
Business miles begin when you leave your regular workplace and travel somewhere else for work. Two situations expand that:
- Temporary work locations. If you have a regular office but drive to a temporary work site expected to last one year or less, home-to-site mileage counts as business.
- Home office as principal workplace. If your home qualifies as your principal place of business, travel from home to any other work location in the same trade or business counts as deductible transportation, regardless of distance.
An employer running either reimbursement method needs a written policy defining which trips qualify. One employee logging commuting miles as business miles creates a substantiation problem that touches the whole plan.
What Happens When a Plan Fails
Payments that don’t satisfy accountable plan rules are treated as nonaccountable plan payments. The employer must include the full amount in the employee’s gross income, report it as wages on Form W-2, and withhold and pay federal income tax, FICA, FUTA, and any other applicable employment taxes.2eCFR. 26 CFR 1.62-2 – Reimbursements and Other Expense Allowance Arrangements
Timing depends on which requirement failed. If the plan’s structure is sound and an employee simply misses a deadline, only that unsubstantiated or unreturned amount becomes taxable, no later than the first payroll after the deadline. If the plan itself fails one of the three core requirements, every payment under the arrangement is taxable when paid.
The IRS pays particular attention to arrangements that recharacterize salary as reimbursement. Revenue Ruling 2012-25 walked through scenarios where an employer routed part of what was really wages through a supposed accountable plan, and the IRS treated the whole arrangement as nonaccountable because the business-connection requirement wasn’t genuinely met.7Internal Revenue Service. Internal Revenue Bulletin 2012-37 If the reimbursement amount doesn’t actually move with the employee’s business expenses, expect it to be recharacterized on audit.
You Can No Longer Deduct What Isn’t Reimbursed
Before 2018, employees who weren’t fully reimbursed could claim unreimbursed vehicle expenses as a miscellaneous itemized deduction subject to a 2-percent-of-AGI floor. The Tax Cuts and Jobs Act suspended that deduction, and the One Big Beautiful Bill Act made the suspension permanent. Notice 2026-10 confirms that the business standard mileage rate cannot be used to claim an itemized deduction for unreimbursed employee travel expenses.5Internal Revenue Service. Notice 2026-10
A few narrow categories keep the deduction as an adjustment to gross income on Schedule 1: members of a reserve component of the Armed Forces, state or local government officials paid on a fee basis, qualified performing artists, and eligible educators. Everyone else absorbs unreimbursed business driving with no tax relief. That shift makes a properly designed accountable plan the only way most employees will see any tax benefit from work-related driving.
State Reimbursement Laws Are a Separate Question
Federal tax law doesn’t require employers to reimburse vehicle expenses. It only sets the framework for making reimbursements tax-free when an employer chooses to offer them. Some states go further and require reimbursement of necessary business expenses under state labor law. Those laws generally don’t set a specific rate, so employers in those states commonly use the IRS standard mileage rate to satisfy the obligation. If your state mandates reimbursement and your employer isn’t paying, that’s a wage claim under state law and sits outside the federal tax rules described here.