Heavy Vehicle Tax Deduction: Section 179 Limits and Bonus Depreciation

A business that buys a vehicle rated over 6,000 pounds gross vehicle weight and uses it more than 50% for business can generally write off the entire cost in the year the vehicle is placed in service. That result comes from stacking two provisions: the Section 179 expensing election and 100% bonus depreciation, which the One Big Beautiful Bill permanently restored for property acquired after January 19, 2025.¹ The heavy vehicle tax deduction is one of the largest first-year write-offs available to a small or mid-size business, but it comes with sharp edges: an SUV sub-cap, a business-use test that keeps applying every year, and recapture rules that bite when circumstances change.

What Counts as a Heavy Vehicle

The dividing line is the vehicle’s Gross Vehicle Weight Rating, the maximum loaded weight the manufacturer certifies the vehicle to handle. Federal tax law defines a “passenger automobile” as a four-wheeled vehicle rated at 6,000 pounds or less, and passenger automobiles are subject to strict annual depreciation caps. Vehicles rated above 6,000 pounds fall outside that definition and escape those caps.²

Most full-size pickups, cargo vans, and larger SUVs clear the threshold, but plenty of models sit right at the line. The GVWR is printed on the sticker inside the driver’s-side door jamb. Check it before you rely on the deduction. GVWR includes the vehicle plus its maximum passengers and cargo, so it’s almost always higher than curb weight.

The 50% Business-Use Test

A heavy vehicle qualifies for accelerated deductions only if it is used more than 50% for business in each year you claim depreciation. The rule comes from the listed property provisions, which single out vehicles for closer scrutiny because of the potential for personal use.² The deduction is then scaled to the actual business-use percentage. A $70,000 truck used 80% for business gives you a depreciable basis of $56,000.

Commuting doesn’t count. Driving from home to a regular workplace is personal even for the self-employed. Trips between job sites, to clients, and on supply runs are business. A contemporaneous mileage log separating business, commuting, and personal miles is effectively required to survive an audit.

Section 179 Limits for 2026

Section 179 lets a business deduct the full price of qualifying equipment in the year it is placed in service instead of depreciating it over several years. For tax years beginning in 2026, the overall cap is $2,560,000. That limit begins phasing out dollar-for-dollar once total qualifying purchases for the year exceed $4,090,000 and disappears entirely at $6,650,000.³

Heavy SUVs face a tighter ceiling. Even when the SUV clears 6,000 pounds GVWR, the Section 179 deduction on it is capped at $32,000 for 2026.³ The SUV cap targets passenger-style vehicles specifically. A pickup with a cargo bed at least six feet long, a van seating more than nine passengers, or a van with no rear seating behind the driver is not classified as an SUV for this purpose and can use the full $2,560,000 limit.

One further guardrail: your Section 179 deduction for the year cannot exceed your total taxable income from active trades or businesses.⁴ The deduction can zero out business income but not create a net loss. Anything you can’t use carries forward to the next year.

How Bonus Depreciation Stacks on Top

Bonus depreciation had been phasing down: 80% in 2023, 60% in 2024, 40% in 2025, and 20% scheduled for 2026. The One Big Beautiful Bill reset that schedule. For property acquired after January 19, 2025, the law provides a permanent 100% first-year depreciation deduction.¹

The practical effect is that whatever cost is left after a Section 179 election can be wiped out through bonus depreciation. For a heavy SUV, the sequence is: take the $32,000 Section 179 deduction, then apply 100% bonus depreciation to the rest of the depreciable basis. The full cost attributable to business use is deductible in year one. For qualifying trucks and vans that aren’t subject to the SUV cap, Section 179 alone often absorbs the entire purchase price.

Why the Weight Threshold Matters

Vehicles at or below 6,000 pounds GVWR are treated as passenger automobiles and hit annual depreciation caps that flatten the first-year write-off. For a lighter vehicle placed in service in 2026 that is eligible for bonus depreciation, the first-year deduction is limited to $20,300.⁵ A $50,000 sedan used entirely for business takes years to fully depreciate under those caps.

A $60,000 pickup rated over 6,000 pounds and used 100% for business, by contrast, can be fully deducted in year one. That gap is why the GVWR sticker often drives the purchase decision.

When Business Use Drops or You Sell

If business use falls to 50% or below in any later year, two things happen. The IRS calculates the difference between the accelerated depreciation you already claimed and what you would have been entitled to under straight-line depreciation, and adds that difference back to your income as recapture.⁶ From that point on, all remaining depreciation on the vehicle switches to the alternative depreciation system, which uses straight-line over a longer recovery period.

Selling a heavily depreciated vehicle triggers a second recapture. Because prior deductions reduced your basis, any sale price above the adjusted basis is a gain, and that gain is taxed as ordinary income up to the total depreciation you claimed.⁷ Buy a truck for $70,000, deduct the whole cost, sell it three years later for $35,000, and the entire $35,000 is ordinary income because your basis is zero. The deduction is still valuable for the deferral, but it isn’t free money, and the eventual sale is part of the planning.

Filing and Documentation

Heavy vehicle deductions are claimed on Form 4562, which covers depreciation, amortization, and Section 179 elections.⁸ Part I is where the Section 179 election goes with the vehicle description and dollar amount. Part V asks for total miles, business miles, personal miles, commuting miles, and the evidence behind those numbers. Sole proprietors attach the form to Schedule C, partnerships to Form 1065, and corporations to Form 1120.

Records to keep on file:

A contemporaneous mileage log separating business, commuting, and personal miles for each year.
Purchase documents showing the total cost, including sales tax and delivery fees.
The vehicle identification number, which pins down the exact make, model, and weight rating.
The date the vehicle was first available and ready for business use, which is not always the purchase date.

Keep the supporting records for at least three years after filing, which is the standard period for the IRS to assess additional tax.⁹ The assessment window stretches to six years if income is underreported by more than 25%, so longer retention is reasonable when the year included a large heavy-vehicle deduction.

1
Internal Revenue Service. Treasury, IRS Issue Guidance on the Additional First Year Depreciation Deduction Amended as Part of the One Big Beautiful Bill
2
Office of the Law Revision Counsel. 26 USC 280F – Limitation on Depreciation for Luxury Automobiles; Limitation Where Certain Property Used for Personal Purposes
3
Internal Revenue Service. Rev. Proc. 2025-32
4
Office of the Law Revision Counsel. 26 USC 179 – Election to Expense Certain Depreciable Business Assets
5
Internal Revenue Service. Rev. Proc. 2026-15
6
Office of the Law Revision Counsel. 26 U.S. Code 280F – Limitation on Depreciation for Luxury Automobiles; Limitation Where Certain Property Used for Personal Purposes
7
Office of the Law Revision Counsel. 26 USC 1245 – Gain from Dispositions of Certain Depreciable Property
8
Internal Revenue Service. Instructions for Form 4562 – Depreciation and Amortization (Including Information on Listed Property)
9
Internal Revenue Service. Topic No. 305, Recordkeeping