Vehicle tax write-offs: what they're really worth

"Buy a truck before December 31" is the most common year-end tax advice there is. A vehicle your business needs can be a real deduction — sometimes a large one in the first year. But a deduction gives back your tax rate on the money spent, never more. Here's how the write-off works, and how to tell whether it pays.

Two ways to deduct driving

  • The standard mileage rate — a set amount per business mile that covers gas, insurance, repairs and depreciation. Simple, and often the better deal for an inexpensive or high-mileage car. Work out your miles →
  • Actual costs — the business share of gas, insurance, repairs, registration and interest, plus depreciation on the vehicle itself. This is where buying a vehicle creates a large deduction.

Either way only the business share counts: if 80% of the miles are for business, 80% of the costs are deductible. Commuting doesn't count as business use.

Buying a vehicle: it depends on the weight

The tax code treats cars and light trucks differently from heavy vehicles. The dividing line is the gross vehicle weight rating on the driver's door sticker: 6,000 pounds.

VehicleFirst-year write-off, 100% business useAfter that
Car, light SUV or light truck — 6,000 lb or lessCapped at $20,300 with bonus depreciation$19,800, then $11,900, then $7,160 a year until it's fully deducted
Heavy SUV — over 6,000 and up to 14,000 lbUp to the full cost with bonus depreciation (Section 179 alone stops at $32,000)Nothing left, if it was all taken the first year
Heavy pickup (over 6,000 lb) with a bed of 6 feet or more, or a van seating more than 9 behind the driverUp to the full cost, under Section 179 or bonus depreciationNothing left, if it was all taken the first year

Those are 2026 figures. The caps shrink with business use — at 80% business use, the first-year cap for a car is 80% of $20,300. Bonus depreciation is back to 100% for vehicles acquired after January 19, 2025, which is why a heavy SUV can be written off in the year it's bought.

The 50% test

Section 179 and bonus depreciation are only available if the vehicle is used more than 50% for business. At 50% or less, it's depreciated slowly over several years. And if business use falls to 50% or below in a later year, part of the write-off you already took is added back to your income. Keep a mileage log from the first day — it's what proves the percentage.

The arithmetic that matters

A deduction lowers your taxable income; it doesn't refund the purchase. At a 30% combined tax rate, a $60,000 vehicle bought for the business saves at most $18,000 in tax — and costs $42,000 that you'd otherwise still have. That's why, in our sample report, "buying a vehicle for the deduction" is markedDoesn't fit for a business whose driving is already covered by a mileage reimbursement.

It's a good deal only when the business needs the vehicle anyway. Then the question isn't whether to buy, but how to deduct it — and a large first-year write-off is worth having.

What would it really cost?

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    When you sell it

    Depreciation you took comes back when you sell: the part of the sale price up to the depreciation you claimed is taxed as ordinary income. A large first-year write-off moves tax to later more than it removes it. How recapture works.

    If you own an S corporation

    You can own the vehicle personally and have the corporation reimburse your business miles under an accountable plan, or have the corporation own it. If the corporation owns it, your personal use of it is a taxable fringe benefit that belongs on your W-2. Which is better depends on the vehicle and the miles — worth working out with your CPA before you buy.

    When it doesn't fit

    • You're buying it for the deduction. You spend a dollar to save 30 cents.
    • Business use is 50% or less, or mostly commuting.
    • Your driving is already covered by the mileage rate on a car you own.

    Whether a vehicle purchase makes sense for your business, and how to deduct it, is a question for your CPA or tax attorney.

    Sources

    General information, not advice for your situation. Whether a strategy fits depends on your facts — talk to your CPA or tax attorney about whether you qualify before you put it in place. Your accountant remains responsible for your return.

    Know where yours stands, all year.

    OpenYear reads your books, shows which strategies fit your business and why, and keeps the records each one needs — ready for your accountant. It's built for owner-operated S corporations.