You can switch from actual expenses to the standard mileage rate only if you used the standard mileage rate in the very first year you placed the vehicle in business service. If you claimed actual expenses that first year, the IRS treats it as a permanent election, and you’re locked into actual expenses for as long as you own or lease that vehicle.1Internal Revenue Service. Topic No. 510, Business Use of Car For context on what’s at stake, the 2026 business standard mileage rate is 72.5 cents per mile.2IRS.gov. 2026 Standard Mileage Rates
Why the First Year Decides Everything
The rule is binary and it turns on one tax year: the first year the vehicle was available for business use. Pick the standard mileage rate that year and you keep your options open in later years. You can move to actual expenses, move back to the mileage rate, and alternate as the math changes.3Internal Revenue Service. Publication 463 (2025), Travel, Gift, and Car Expenses
Pick actual expenses in year one and that flexibility is gone. There’s no workaround and no way to undo it. Many taxpayers don’t feel the effect until later, when high annual mileage would have made the standard rate more valuable than the receipts they’ve been tracking.1Internal Revenue Service. Topic No. 510, Business Use of Car
You didn’t file a form or check a box to make that election. Your method was set by how you filled out the return that first year. Whichever calculation appeared on that Schedule C is the choice the IRS holds you to.
Leased Vehicles: Even Less Flexibility
If your vehicle is leased and you started with actual expenses, the door is closed for that lease. You cannot switch to the standard mileage rate at any point during the lease. The mirror rule is just as strict: if you started the lease using the standard mileage rate, you must keep using it for the entire lease period, including any renewals.3Internal Revenue Service. Publication 463 (2025), Travel, Gift, and Car Expenses
With a leased car there is no back-and-forth. Whichever method you used in the first year of the lease is the method you use until the lease ends.
What About the Other Direction?
Many people asking this question actually have the opposite situation: they used the standard mileage rate the first year and now want to switch to actual expenses because a big repair, insurance jump, or new financing has made the receipts more valuable. That switch is allowed, and you can make it in any later year.3Internal Revenue Service. Publication 463 (2025), Travel, Gift, and Car Expenses
One restriction catches people off guard. When you move from the mileage rate to actual expenses, you cannot depreciate the vehicle using MACRS or any accelerated method. You must use straight-line depreciation over the vehicle’s estimated remaining useful life. That spreads the deduction evenly rather than front-loading it, so the depreciation piece in your first year of actual expenses is smaller than it would have been if you’d started with actual expenses on day one. Regular annual depreciation limits for passenger vehicles still apply on top of that.3Internal Revenue Service. Publication 463 (2025), Travel, Gift, and Car Expenses
There’s also a basis issue to plan for. Every year you claimed the standard mileage rate, part of that rate was a built-in depreciation component that reduces your cost basis in the vehicle. For 2026 that component is 35 cents of the 72.5-cent rate; it was 33 cents in 2025 and 30 cents in 2024.2IRS.gov. 2026 Standard Mileage Rates When you switch to actual expenses, your depreciable basis is already lower by the accumulated total, which shrinks your going-forward depreciation deductions. It also shows up later: when you sell or trade the vehicle, a lower basis means a larger taxable gain.
Depreciation Choices That Also Lock You In
Starting with the standard mileage rate keeps your options open only if you don’t take certain depreciation steps in a later year. Three specific elections will block you from ever returning to the standard mileage rate for that vehicle:1Internal Revenue Service. Topic No. 510, Business Use of Car
- Claiming MACRS depreciation in any year
- Expensing any part of the vehicle’s cost under Section 179
- Using any accelerated depreciation method other than straight-line
The reason is that the standard mileage rate already carries a depreciation component inside it. The IRS won’t allow accelerated depreciation in some years and mileage-rate depreciation in others on the same vehicle. Once you’ve used any of those tools, you’re committed to actual expenses for the rest of that vehicle’s business life.3Internal Revenue Service. Publication 463 (2025), Travel, Gift, and Car Expenses
If You’re Locked Into Actual Expenses, Make Them Count
When switching to the mileage rate isn’t available, the deduction still lives or dies on your records. Keep organized documentation of every operating cost tied to the vehicle: fuel, oil changes, tires, repairs, insurance premiums, registration fees, and loan interest. You’ll apply your business-use percentage to those totals to determine the deductible share.3Internal Revenue Service. Publication 463 (2025), Travel, Gift, and Car Expenses
You still need a mileage log even when you’re using the actual expense method, because that’s how you prove the business-use percentage. Record each business trip at or near the time it happens: date, starting point, destination, business purpose, and miles driven. Odometer readings at the start and end of the tax year establish your annual total, which you divide between business and personal use. Without those numbers, the business-use percentage you claim has little to support it.
The practical lesson for anyone starting fresh with a new vehicle: when the choice is genuinely close in year one, the standard mileage rate is the safer election, because you can always move to actual expenses later. Going the other way isn’t an option.