Mileage vs Actual Expense Calculator

Compare methods with the midyear rate change

Self-employed taxpayers generally compare an optional standard mileage allowance with the business share of actual vehicle expenses. The unusual part of 2026 is timing: business miles from January 1 through June 30 use 72.5 cents per mile, while miles from July 1 through December 31 use 76 cents per mile. The IRS raised the rate midyear after fuel-cost increases. Both periods appear in the IRS standard mileage rate table, citing IR-2025-128 and IR-2026-29.

Enter business miles in the half when they were driven. The standard result multiplies each period by its rate, then adds business parking and tolls. Do not average the two rates unless your records actually support an even mileage split.

The actual method first totals gas, insurance, repairs, registration, and either lease cost or allowable depreciation. It multiplies that total by business-use percentage: business miles divided by total annual vehicle miles. Business use is capped at 100% if inconsistent entries put business miles above total miles. Parking and tolls are then added because they are not part of ordinary vehicle operating costs.

For a worked 2026 example, enter 6,000 business miles from January through June, 6,000 from July through December, 18,000 total vehicle miles, $10,300 of eligible entered vehicle costs, and $500 of business parking and tolls. Standard mileage is 6,000 × the 2026 first-half $0.725 rate + 6,000 × the 2026 second-half $0.76 rate + $500 = $9,410. Business use is 12,000 ÷ 18,000 = 66.67%, so actual expense is $10,300 × 66.67% + $500 = $7,366.67 after rounding. Standard mileage is larger by $2,043.33, subject to method eligibility and records.

Rates current as of September 2026.

Actual expense requires tax-ready inputs

“Lease cost or depreciation” is one box only to make the comparison usable; those alternatives are not interchangeable. Owners must calculate allowable depreciation under vehicle limits, conventions, business-use rules, and prior elections. Lessees may need an inclusion amount. Entering the purchase price as current-year depreciation would overstate the result. IRS Topic 510 and Publication 463 explain vehicle expenses and recordkeeping.

Use annual costs for the same vehicle and year. Do not include personal parking tickets, fines, loan principal, or costs already reimbursed under an accountable plan. Interest and certain personal-property taxes can have separate treatment and are intentionally omitted from this focused input set.

Method choice is not always reversible

The common warning that “you can never switch back after actual expenses” is too broad. For a vehicle you own, you generally must choose standard mileage in the first year it is available for business use to preserve the option. If you start with standard mileage, you may use actual expenses in a later year, but straight-line depreciation rules apply. If you use actual expenses in the first business-use year, standard mileage is generally unavailable later. A leased vehicle using standard mileage generally must use it for the entire lease period. The current Form 2106 instructions summarize those restrictions.

The larger displayed method is only a numerical winner for the entries supplied. A valid deduction also needs adequate records showing date, destination, business purpose, and mileage. Ordinary commuting is generally personal even when work is performed at the destination. Mixed-use vehicles need complete total-mile records, not only a log of claimed trips.

Cost per business mile divides the larger modeled deduction by business miles. It is a comparison metric, not another deduction. When business miles are zero, the calculator reports zero per mile.

Common mistakes and edge cases

• Counting ordinary commuting as business mileage can overstate either method.
• Entering a vehicle purchase price as one year's depreciation ignores limits, conventions, and elections.
• Leaving personal miles out of total mileage inflates the actual-expense business-use percentage.
• Mixing costs from two vehicles with mileage from one vehicle produces a comparison for neither.
• Choosing actual expenses in the first business-use year, or using a lease inconsistently, can remove later standard-mileage flexibility.

What to do next

Reconcile the mileage log to beginning- and end-of-year odometer records and separate each vehicle. Confirm that trips have dates, destinations, and business purposes. Calculate allowable depreciation or lease inclusion outside this simplified tool before entering that box. Compare methods only after checking first-year eligibility, then save the calculation and the 2026 IRS rate source with the return records.

Disclaimer: This calculator is informational only and is not tax or legal advice. Confirm method eligibility, substantiation, depreciation, and vehicle-specific limits before filing.