How to Calculate Mileage Cost: IRS Rate vs. Actual Expenses

To calculate your mileage cost, add every dollar you spent on the vehicle over the year — fixed costs like insurance and registration plus variable costs like fuel and repairs — and divide by the total miles you drove. That gives you your true per-mile cost. For tax purposes, you then compare that figure against the 2026 IRS standard mileage rate of 72.5 cents per mile for business driving to see which method produces the larger deduction.¹

Both numbers matter, and for different reasons. Your personal per-mile cost tells you whether a delivery gig is actually profitable, what to charge a client for travel, and when a car has crossed from useful asset to money pit. The IRS rate tells you what the government will let you write off. They rarely match exactly, and the gap between them is where the real decisions get made.

Your Personal Cost Per Mile

The formula is simple: total vehicle spending divided by total miles driven. If your car cost $9,600 to operate over 16,000 miles, you’re at 60 cents per mile. Everything else is just making sure you’ve captured all the costs.

Fixed Costs

These hit your budget whether the car moves or not: insurance premiums, registration and license fees, loan interest, and depreciation. Aggregating them gives you the baseline cost of simply keeping the vehicle legal and operational. For most owners, this category runs several thousand dollars per year before a single mile is driven.

Variable Costs

Variable expenses scale with use. Fuel is the obvious one. Include oil changes, tire replacements, brake work, and any repairs caused by wear or mechanical failure. Collect every receipt throughout the year.

Tracking this number year over year also reveals when a vehicle is becoming a money pit. A car costing 45 cents per mile at 60,000 miles might cost 75 cents per mile at 130,000 miles once major repairs start piling up. That is the kind of insight that tells you when to replace a vehicle rather than keep sinking money into it.

The IRS Standard Mileage Rate

The simplest tax approach is multiplying your business miles by the IRS standard rate. For 2026, that rate is 72.5 cents per mile for business use, 20.5 cents per mile for medical travel, and 14 cents per mile for charitable driving.¹ The charitable rate is set by statute and rarely changes; the business and medical rates are adjusted annually based on a study of vehicle operating costs.

The business rate covers depreciation, insurance, repairs, gas, and general wear. Parking fees and tolls tied to a business trip are deductible separately on top of the standard rate.²

A self-employed consultant who drives 12,000 business miles in 2026 would calculate: 12,000 × $0.725 = $8,700, plus any parking and tolls. No fuel receipts, no insurance math.

One detail worth knowing: 35 cents of the 72.5-cent business rate is attributed to depreciation.¹ That matters when you eventually sell or trade in the vehicle, because the IRS treats those depreciation cents as having reduced your cost basis, which can create a taxable gain on disposal even if the car lost value in the real world.

The Actual Expense Method

The alternative is tracking every dollar you spend on the vehicle and deducting the business-use percentage. Deductible costs include gas, oil, tires, repairs, insurance, registration fees, license plates, loan interest, lease payments, garage rent, parking, tolls, and depreciation. If you are self-employed, the business portion of state and local personal property taxes on the vehicle is also deductible on Schedule C.²

To figure your business percentage, divide business miles by total miles driven during the year. Drove 20,000 total miles with 14,000 for business? Your business-use percentage is 70%. Apply that 70% to your total vehicle costs.³

Running the Comparison

Say your total vehicle costs for the year come to $10,800 and you use the car 70% for business. Actual expense deduction: $7,560. Now run the standard rate on those same 14,000 business miles: 14,000 × $0.725 = $10,150. Standard rate wins by a wide margin.

Flip the numbers and the answer flips. A newer vehicle with a big loan, high insurance, and heavy depreciation may produce actual costs well above the standard rate, especially at lower annual mileage. An older, paid-off, fuel-efficient car driven hard for work almost always does better on the standard rate. Run the comparison every year — fuel prices, repairs, and driving patterns all move.

The First-Year Choice That Locks You In

The method you pick the first year a vehicle is available for business use controls what you can do later, and this is where people lose money without realizing it.

Choose the standard mileage rate in year one and you keep your options open. In later years you can switch to actual expenses, then back again as it suits you.²

Choose actual expenses in year one and claim MACRS depreciation or a Section 179 deduction, and you are locked into actual expenses for the life of that vehicle. You can never switch to the standard mileage rate for that car.²

There is also a softer penalty for switching later: if you start with the standard rate and change to actual expenses in a later year, you must use straight-line depreciation over the car’s remaining useful life instead of accelerated MACRS.³ That typically produces a smaller annual depreciation deduction than MACRS would have given from the start.

Two more restrictions on the standard rate: you cannot use it if you operate five or more vehicles simultaneously for business, and if you lease a vehicle using the standard rate, you must continue using the standard rate for the entire lease period.⁴

Which Miles Actually Count

Driving from your home to your regular workplace and back is commuting, and the IRS treats it as a personal expense regardless of distance.² A 50-mile commute is still a commute.

What counts as deductible business travel: trips from your regular workplace to a client site, travel between two work locations, and trips to a temporary work location expected to last one year or less.² If your home qualifies as your principal place of business under the home office rules, the math changes significantly: every trip from your home to a client or other work location becomes deductible business mileage rather than commuting.⁵ For self-employed people who work from home, that distinction alone can add thousands of deductible miles per year.

Who Can Actually Claim the Deduction

If you are a W-2 employee, you generally cannot deduct business mileage on your federal return. The Tax Cuts and Jobs Act of 2017 suspended the miscellaneous itemized deduction for unreimbursed employee expenses starting in 2018, and the One Big Beautiful Bill Act of 2025 made that suspension permanent. If your employer does not reimburse your mileage, you have no federal write-off.

Self-employed individuals and independent contractors are the primary beneficiaries. File Schedule C and you can deduct vehicle expenses using either the standard mileage rate or the actual expense method.⁴ Armed Forces reservists, qualified performing artists, and fee-basis state or local government officials can still use Form 2106 to claim vehicle expenses.⁶

For W-2 workers, employer reimbursement is the only recovery route. When the employer operates an accountable plan — requiring a business purpose, adequate accounting within a reasonable time, and return of excess amounts — the reimbursement stays out of your taxable wages. A flat car allowance with no mileage log or receipt requirement is a nonaccountable plan, and every dollar of it becomes taxable income subject to payroll tax.² Most accountable plans reimburse at or below the IRS rate of 72.5 cents per mile for 2026.¹

Keeping a Log That Holds Up

The IRS requires a contemporaneous record, meaning you logged the trip at or near the time it happened rather than reconstructing it from memory later. Each entry needs five elements: date, starting point and destination, specific business purpose, miles driven, and your odometer readings at the start and end of the year.⁶

Vague entries are where deductions die in an audit. “Client meeting” will not hold up. “Met with Sarah Chen at Acme Corp to discuss Q2 contract renewal” will. “About 20 miles” is a red flag; 18.3 miles based on an odometer or GPS reading is defensible. A mileage app that captures your route in real time produces the strongest documentation.

You do not technically need a receipt for expenses under $75, but the IRS requires receipts for any single expense of $75 or more and for all lodging costs.⁶ Keeping every receipt digitally costs almost nothing and removes any question about documentation.

Record your odometer at the start and end of each tax year, and again whenever you place the vehicle into service for business or take it out of service.² Those bookend readings are what the IRS uses to verify your total mileage and business-use percentage, and forgetting to snap a photo of your odometer on January 1 creates an outsized headache later.

1
Internal Revenue Service. 2026 Standard Mileage Rates, Notice 2026-10
2
Internal Revenue Service. Publication 463 (2025), Travel, Gift, and Car Expenses
3
Internal Revenue Service. Topic No. 510, Business Use of Car
4
Internal Revenue Service. Instructions for Schedule C (Form 1040)
5
Internal Revenue Service. Instructions for Form 2106 (2025)
6
Internal Revenue Service. Instructions for Form 2106 (2025)