It depends who you are:
- Self-employed / sole proprietor / independent contractor — Yes. Business miles are deductible on Schedule C, using either the standard mileage rate or actual expenses (§162).
- W-2 employee, unreimbursed — Generally no. §67(g) suspended the miscellaneous itemized deductions this used to fall under, and the One Big Beautiful Bill Act (P.L. 119-21) made that suspension permanent. Narrow above-the-line exceptions survive under §62(a)(2): Armed Forces reservists, qualified performing artists, fee-basis state/local government officials, and impairment-related work expenses.
- Employee reimbursed under an accountable plan — Nothing to deduct. The reimbursement isn't income, so there's nothing left to claim.
Which miles count: Commuting (home ↔ regular workplace) is never deductible. Deductible business miles include job site to job site, a temporary work location (expected to last one year or less — Rev. Rul. 99-7), and, if you have a qualifying home office that is your principal place of business, trips from there to other work locations (the "home-office pivot").
You need a log: Vehicles are listed property under §280F(d)(4), so §274(d) strict substantiation applies (date, mileage, destination, business purpose). The Cohan estimation rule does NOT rescue a missing mileage log.
2026 is a split rate year (US): miles driven Jan 1–Jun 30, 2026 use 72.5¢/business mile (Notice 2026-10); miles on or after Jul 1, 2026 use 76¢ (Announcement 2026-11). A 2026 return needs both.
Outside the US: UK HMRC Approved Mileage Allowance Payments are 55p/mile for the first 10,000 business miles and 25p after for 2026/27 (up from 45p), with Mileage Allowance Relief available to employees. Canada uses CRA per-km rates (73¢ first 5,000 km, 67¢ after for 2026).
Full guide: Is Mileage Tax Deductible?. For the amount, use the mileage calculator. Estimates — confirm with your tax professional.