You generally cannot switch from actual expenses to the standard mileage rate on a business vehicle. The IRS requires you to elect the standard mileage rate in the first year you place the vehicle in business service; if you filed that first return using the actual expense method, the standard rate is permanently unavailable for that car.1Internal Revenue Service. Topic No. 510, Business Use of Car The switch in the other direction — from standard mileage to actual expenses — is allowed for vehicles you own, subject to depreciation restrictions.
The First Year Is a Binding Election
The IRS treats the method you use on your first return for a given vehicle as a lasting choice. To ever apply the standard mileage rate to a car you own, you must select it the first year the car is available for business use.1Internal Revenue Service. Topic No. 510, Business Use of Car Miss that window by claiming actual expenses, and you have forfeited standard mileage for the life of that vehicle. Later changes in your driving patterns, fuel prices, or repair bills do not reopen the choice.
For 2026, the standard mileage rate is 72.5 cents per mile for business driving.2Internal Revenue Service. IRS Sets 2026 Business Standard Mileage Rate at 72.5 Cents Per Mile That single rate is meant to cover fuel, insurance, repairs, depreciation, and the other operating costs a driver would otherwise itemize under the actual expense method.3Internal Revenue Service. Publication 463, Travel, Gift, and Car Expenses Parking fees and tolls tied to business use stay separately deductible under either method.1Internal Revenue Service. Topic No. 510, Business Use of Car
Accelerated Depreciation Locks Out Standard Mileage Permanently
Even if you did not formally choose “actual expenses” in year one, certain depreciation elections carry the same consequence. Revenue Procedure 2010-51 identifies four depreciation methods that permanently disqualify a vehicle from ever using the standard mileage rate:4Internal Revenue Service. Revenue Procedure 2010-51
- MACRS, the Modified Accelerated Cost Recovery System, which is the default depreciation system for business property placed in service after 1986.
- A Section 179 election to expense part or all of the vehicle’s cost in the year of purchase.
- Bonus depreciation under Section 168(k), which allows a large first-year write-off.
- ACRS, the older Accelerated Cost Recovery System, for property placed in service before 1987.
Claim any of these even once, and the standard mileage rate is off the table for that vehicle. The rule prevents double-dipping: the standard rate already builds in its own straight-line depreciation component, so allowing accelerated depreciation first and standard mileage later would count the vehicle’s cost against income twice.
Leased Vehicles: No Switching in Either Direction
Leases follow a stricter rule than owned vehicles. Whichever method you pick in the first year of the lease applies for the entire lease term, including any renewal periods.1Internal Revenue Service. Topic No. 510, Business Use of Car There is no switching from actual to standard, and no switching from standard to actual, once the lease begins. The initial choice on a leased car matters more than it does on a purchased one, because a mismatched method on a multi-year, high-mileage lease can cost thousands in lost deductions with no way to correct it mid-term.
Switching the Other Way: Standard Mileage to Actual Expenses
If you did elect the standard mileage rate in year one on a vehicle you own, you keep flexibility. You can switch to the actual expense method in any later year, and you can move between the two methods in different tax years going forward.1Internal Revenue Service. Topic No. 510, Business Use of Car That flexibility is one-way: starting with standard mileage preserves the option; starting with actual expenses closes it.
The catch on switching to actual expenses is depreciation. By using the standard rate, you excluded the vehicle from MACRS.4Internal Revenue Service. Revenue Procedure 2010-51 When you later move to actual expenses, you must use straight-line depreciation over the car’s remaining estimated useful life, subject to the annual depreciation caps for passenger vehicles.5Internal Revenue Service. Instructions for Form 2106 (2025) MACRS, Section 179, and bonus depreciation are all unavailable on a vehicle previously deducted under the standard mileage rate.
Your Basis Has Already Been Reduced
Part of the standard mileage rate counts as depreciation, and that portion reduces your vehicle’s tax basis each year, even though the rate looks like a flat per-mile number. For 2026, 35 cents of the 72.5-cent rate is the depreciation component.6Internal Revenue Service. 2026 Standard Mileage Rates The IRS requires you to reduce basis by that per-mile amount multiplied by your business miles for every year you used the standard rate.7Internal Revenue Service. Revenue Procedure 2019-46 That reduced basis is what you start from when you compute straight-line depreciation under the actual expense method after a switch.
What Happens If You Claim Standard Mileage When You Cannot
Using the standard mileage rate on a vehicle that does not qualify — because you started with actual expenses, claimed accelerated depreciation, or otherwise fall outside the rules — can lead the IRS to disallow the deduction. If the disallowance produces a substantial understatement of tax, you may face an accuracy-related penalty of 20% of the underpaid amount.8Internal Revenue Service. Accuracy-Related Penalty For an individual, a substantial understatement means an understatement greater than 10% of the tax owed, or $5,000, whichever is larger. Keeping your original return, records of the method you elected in year one, and a contemporaneous mileage log are the practical defenses if the question ever comes up.