How to Write Off a Vehicle Purchase as a Sole Proprietor

To write off a vehicle purchase as a sole proprietor, you deduct the business-use share of the vehicle on Schedule C, choosing between the standard mileage rate and the actual expense method (which lets you depreciate the vehicle itself). For a passenger car placed in service in 2026, first-year depreciation is capped at $20,300 with bonus depreciation. For a qualifying vehicle over 6,000 pounds gross vehicle weight rating and used more than 50% for business, 100% bonus depreciation can write off the entire cost in year one.

Where the Deduction Lands on Your Return

A sole proprietorship is not a separate tax entity. Business income and expenses go on Schedule C, and the net profit flows into your Form 1040.¹ A vehicle deduction reduces that net profit, which cuts two taxes at once. The first is federal income tax. The second is self-employment tax, which funds Social Security and Medicare at a combined 15.3% on your net earnings. A $10,000 vehicle deduction saves you income tax and roughly $1,530 in self-employment tax on top of it. Sole proprietors comparing methods often forget the second number.

Start With Your Business Use Percentage

Every vehicle deduction is scaled by the share of miles you drive for business. Drive 15,000 miles in a year with 10,000 for business, and your business use percentage is 67%. That percentage multiplies against every deductible cost under either method.²

The IRS treats commuting as personal. Driving from home to a regular place of business is never deductible, however far the trip.³ Rent an office or studio and drive there daily, and that daily trip is a commute. Miles between business locations during the workday, trips to clients, and travel to temporary job sites count as business miles. If you have a qualifying home office, trips from home to a business destination are deductible because your home is your principal place of business.

Business use must be more than 50% to claim Section 179 expensing, bonus depreciation, or accelerated MACRS. Fall to 50% or below and you’re limited to straight-line depreciation, and you may owe recapture on excess deductions from earlier years.

Standard Mileage Rate or Actual Expenses

The two methods produce very different deductions, and the choice you make in year one constrains what you can do later.

Standard Mileage Rate

Multiply your business miles by the IRS rate: 72.5 cents per mile for 2026.⁴ The rate is designed to cover gas, insurance, repairs, depreciation, and wear. You don’t track those items separately. Tolls and parking for business trips are deductible on top of the mileage rate.²

You must elect the standard mileage rate in the first year the vehicle is placed in service for business.² Doing so preserves flexibility: you can switch to actual expenses in a later year. The reverse is not true. Start with actual expenses and claim MACRS, Section 179, or bonus depreciation, and you cannot switch to the standard mileage rate on that vehicle later.

The standard mileage rate is unavailable if you operate five or more vehicles at once in a fleet, and it’s unavailable for vehicles used for hire.²

Even without a depreciation form, part of every business mile is treated as depreciation. For 2026, the depreciation component is 35 cents per mile.⁴ That reduces your basis in the vehicle for the eventual sale.

Actual Expense Method

Track every cost of operating the vehicle and deduct the business-use percentage of each. Deductible items include gas, oil, tires, repairs, insurance, registration fees, loan interest, and depreciation.² The record-keeping is heavier, but the deduction is usually larger, especially for expensive vehicles or high operating costs. Depreciation is usually the biggest line, and that’s where the first-year write-off rules become the deciding factor.

First-Year Write-Off Under Actual Expenses

Two provisions accelerate depreciation into the first year: Section 179 expensing and bonus depreciation. Bonus depreciation was restored to 100% by the One Big Beautiful Bill for property acquired after January 19, 2025.⁵ Both are reported on Form 4562 filed with your Schedule C.⁶ How much of the cost you can actually claim in year one depends entirely on the vehicle’s weight.

Passenger Vehicles Under 6,000 Pounds

Cars, sedans, and lighter trucks under 6,000 pounds GVWR are subject to annual caps that the tax code labels “luxury automobile” limits, though they apply regardless of price or trim.⁷ For vehicles placed in service in 2026, the combined maximum deduction (Section 179 plus bonus plus regular MACRS) cannot exceed:⁸

With bonus depreciation: $20,300 year one, $19,800 year two, $11,900 year three, and $7,160 each year after until fully recovered.
Without bonus depreciation: $12,300 year one, then the same limits above.

Buy a $50,000 sedan used 100% for business, and the cap holds you to $20,300 the first year. The remaining $29,700 unwinds over the following years at the amounts above.

Heavy Vehicles Over 6,000 Pounds

Vehicles with a GVWR above 6,000 pounds are exempt from the passenger caps. That exemption is why heavy SUVs, pickups, and cargo vans dominate business-vehicle tax planning. With 100% bonus depreciation restored, a qualifying heavy vehicle used more than 50% for business can be written off entirely in year one, with one carve-out: sport utility vehicles have a separate Section 179 cap of $32,000 for 2026. Bonus depreciation has no such cap, so a heavy SUV can still reach a full first-year deduction by combining the two. A heavy pickup or van not classified as an SUV avoids even the $32,000 Section 179 restriction.

The threshold is the manufacturer’s gross vehicle weight rating, printed on the label inside the driver’s door jamb. Curb weight doesn’t count. A GVWR of 6,001 pounds or more puts the vehicle in the heavier class.

Records the IRS Expects

Vehicle deductions are among the most frequently challenged items in audits, and weak documentation is usually where they collapse. Regardless of the method you choose, you must substantiate the amount, time, place, and business purpose of each trip.² Records must be contemporaneous. Reconstructing a year of driving at tax time doesn’t meet the standard.

For each business trip, log the date, destination, business purpose, and miles driven. Record the odometer at the start and end of each tax year so you can compute total annual miles and the business-use percentage.² Electronic logs and GPS-based apps are acceptable as long as they capture the required detail.

Actual expense filers also need receipts or statements for fuel, repairs, insurance, loan interest, registration, and every other cost, each showing amount, date, and vendor.² Keep vehicle records at least three years from the later of the filing date or the return’s due date.⁹ Hold depreciation records at least three years past the year you report the vehicle’s sale or disposition, since the IRS needs the full history to verify basis.¹⁰

What You Owe When You Sell or Cut Back Business Use

Depreciation isn’t free money. When you sell a vehicle you’ve been depreciating, the gain is the sale price minus your adjusted basis, and adjusted basis is your original cost reduced by all depreciation claimed.¹¹ Buy a truck for $40,000, claim $30,000 in depreciation, and your basis is $10,000. Sell it for $18,000 and you have an $8,000 gain.

That gain doesn’t get capital gains treatment. Under Section 1245, profit on depreciable personal property is ordinary income to the extent of prior depreciation.¹² This is depreciation recapture, and it applies whether you used actual expenses or the standard mileage rate. The sale is reported on Form 4797.¹³ Standard mileage rate users face the same math: every business mile reduced basis by that year’s depreciation component (35 cents for 2026).⁴

Recapture also fires without a sale. If business use drops to 50% or below in any year after you claimed Section 179, bonus depreciation, or accelerated MACRS, the excess over what straight-line would have given you becomes ordinary income that year, reported on Form 4797, and you switch to straight-line for the remainder of the recovery period.¹³ Write off $20,300 in year one, drop to 40% business use in year two, and the recapture can be substantial. If your business use might drift below 50%, weigh that risk against the appeal of a large first-year deduction. Starting with the standard mileage rate keeps your options open and avoids this exposure entirely.

The Clean Vehicle Credit Is Closed for 2026 Purchases

The new clean vehicle credit and the commercial clean vehicle credit both expired for vehicles acquired after September 30, 2025.¹⁴ A vehicle acquired on or before that date but placed in service in 2026 may still qualify. New purchases in 2026 do not.

1
Internal Revenue Service. Sole Proprietorships
2
Internal Revenue Service. Topic no. 510 – Business Use of Car
3
Internal Revenue Service. Publication 463 – Travel, Gift, and Car Expenses
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Internal Revenue Service. 2026 Standard Mileage Rates
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Internal Revenue Service. One, Big, Beautiful Bill Provisions
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Internal Revenue Service. About Form 4562, Depreciation and Amortization
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Office of the Law Revision Counsel. 26 U.S. Code 280F – Limitation on Depreciation for Luxury Automobiles
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Internal Revenue Service. Rev. Proc. 2026-15 – Depreciation Limitations for Passenger Automobiles
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Internal Revenue Service. How Long Should I Keep Records
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Internal Revenue Service. Topic no. 305, Recordkeeping
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Internal Revenue Service. Topic no. 703, Basis of Assets
12
Office of the Law Revision Counsel. 26 USC 1245 – Gain From Dispositions of Certain Depreciable Property
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Internal Revenue Service. About Form 4797, Sales of Business Property
14
Internal Revenue Service. Commercial Clean Vehicle Credit