How the mileage deduction is calculated
The standard mileage method values your business driving at a flat IRS rate per mile, so you simply multiply your substantiated business miles by the applicable rate instead of tracking every gas, insurance, repair, and depreciation cost. The rate is set annually and bundles all of those operating costs into one figure. For 2025 the rates are 70¢ per business mile, 21¢ for medical and eligible moving, and 14¢ for charity. For Jan–Jun 2026 the rates are 72.5¢, 20.5¢, and 14¢. Effective July 1, 2026, the IRS raised business mileage to 76¢ and medical/eligible moving to 23.5¢, while charity remains 14¢.
The alternative is the actual-expense method, where you total the real costs of operating the vehicle (fuel, oil, tires, insurance, registration, lease payments or depreciation, repairs) and deduct the business-use percentage. The standard rate is simpler and needs only a mileage log; actual expenses can produce a larger deduction for expensive or heavily driven vehicles but require far more recordkeeping.
Worked example
A self-employed consultant drives 12,000 business miles in 2025. Using the standard mileage method, the deduction is 12,000 × $0.70 = $8,400, reported on Schedule C. If that same driver instead documented $9,800 of total vehicle costs and the car was used 70% for business, the actual-expense deduction would be $9,800 × 70% = $6,860 — so here the standard method wins. The right choice depends on the vehicle and the miles, which is why it is worth running both.
Common mistakes & edge cases
Commuting between home and a regular workplace is never deductible — only business trips between work locations, to clients, or for errands count. If you own the vehicle and want the flexibility to switch methods later, you must use the standard mileage rate in the first year the car is placed in service; a leased vehicle that starts on the standard rate must keep it for the entire lease term. Note also that the standard rate includes a depreciation component (33¢ per mile for 2025, 35¢ for 2026) that reduces your vehicle’s basis. Finally, unreimbursed employee mileage is not deductible for most W-2 workers because the Tax Cuts and Jobs Act suspended miscellaneous itemized deductions, a suspension the One Big Beautiful Bill Act made permanent.
Frequently asked questions
Did the IRS change the 2026 mileage rates mid-year?
Yes. The Jan–Jun 2026 rates are 72.5¢ for business and 20.5¢ for medical/eligible moving. For miles on or after July 1, 2026, those rates increase to 76¢ and 23.5¢. Charity remains 14¢ for both periods.
Can a W-2 employee deduct business mileage?
Generally no. The deduction for unreimbursed employee business expenses, including mileage, is suspended for most employees through the TCJA and now permanently under OBBBA. Limited exceptions exist (for example, certain reservists, qualified performing artists, and fee-basis government officials). The better route for employees is an employer accountable-plan reimbursement, which is tax-free.
Do I have to keep a mileage log?
Yes. The IRS requires a contemporaneous record showing the date, destination, business purpose, and miles for each trip. A mileage app or a written log satisfies this; reconstructed or estimated logs are routinely disallowed on audit.