Heavy Truck Depreciation: Section 179, Bonus Depreciation, and MACRS for Trucking

If you buy a $180,000 Peterbilt and use it for business, you can deduct the entire cost in the year you put it on the road. That’s not a typo, and it’s not a loophole. The tax code treats heavy trucks differently from passenger vehicles, and the difference is worth tens of thousands of dollars in the first year. The key is understanding which depreciation method to use, when each one applies, and what happens if you sell the truck later.

Why don’t the luxury auto caps apply to heavy trucks?

Under IRC 280F, the IRS limits how much depreciation you can claim on “listed property” that includes passenger automobiles. For a passenger car placed in service in 2026, the first-year cap is relatively modest ($20,300 with bonus depreciation, $12,300 without). These caps exist because Congress didn’t want business owners writing off luxury sports cars in full the year they bought them.

Heavy trucks escape these caps entirely. The 280F luxury auto limits apply only to passenger automobiles, defined as vehicles with a gross vehicle weight rating (GVWR) of 6,000 lbs or less. Once you cross the 6,000 lb threshold, the caps disappear, with one important qualification.

Vehicles between 6,000 and 14,000 lbs GVWR get partial relief. They’re exempt from the annual depreciation caps, but the Section 179 deduction is limited to approximately $32,000 for SUVs in this weight range. This is the “heavy SUV” provision under IRC 179(b)(5)(A), and it catches pickups and SUVs that qualify by weight but are really passenger vehicles in disguise. A Ford F-250 or a Chevy Suburban falls into this range. You can still claim bonus depreciation on the full cost above the $32,000 (the cap applies only to the Section 179 portion), but it’s a narrower benefit than what’s available for truly heavy equipment.

Vehicles over 14,000 lbs GVWR face no cap at all. No luxury auto limitation, no SUV restriction on Section 179, nothing. A Class 6 box truck, a Class 7 day cab, or a Class 8 Peterbilt or Kenworth tractor qualifies for the full Section 179 deduction (up to the general $2,560,000 limit for 2026) and 100% bonus depreciation with no dollar ceiling. This is where the real benefit lives for owner-operators.

How does Section 179 work for a truck purchase?

IRC 179 lets you deduct the full cost of qualifying business property in the year you place it in service, rather than spreading the deduction over multiple years. For 2026, the maximum Section 179 deduction is $2,560,000, and the deduction begins to phase out dollar-for-dollar when total qualifying property placed in service exceeds $4,090,000. For a single-truck owner-operator, the phase-out is irrelevant. You’d need to buy over $4 million in equipment in one year to trigger it.

The critical limitation of Section 179 is the taxable income cap. Your Section 179 deduction cannot exceed the taxable income from your active trades or businesses. If your Schedule C shows $100,000 of net income before depreciation and you buy a $180,000 truck, Section 179 is capped at $100,000. The remaining $80,000 doesn’t disappear; it carries forward to the next year. But it can’t create or increase a loss in the current year.

This is the single most important difference between Section 179 and bonus depreciation. Section 179 is limited by income. Bonus depreciation is not.

Section 179 also requires an election on your return. The election must be made on a timely filed return (including extensions). You can’t amend to claim it after the filing window closes. The election is made on Form 4562.

What changed with bonus depreciation after the OBBBA?

Before the One Big Beautiful Bill Act (signed July 2025), bonus depreciation was phasing down. The Tax Cuts and Jobs Act of 2017 set 100% bonus depreciation for property placed in service from September 2017 through December 2022, then set a declining schedule that would have reduced it to zero by 2027.

The OBBBA restored 100% bonus depreciation with no scheduled end date, but with a specific effective date. For property acquired after January 19, 2025, the full 100% rate applies under IRC 168(k).

The term “acquired” matters. It means the date you entered into a binding contract to purchase the property, not the date it was placed in service. If you signed a purchase agreement for a truck on February 1, 2025 but didn’t take delivery until April, the acquisition date is February 1, and 100% bonus depreciation applies.

Unlike Section 179, bonus depreciation has no taxable income limitation. It can create or increase a net operating loss (NOL), which carries forward to offset future income. For an owner-operator in a startup year with high equipment costs and lower revenue, this is significant. If you buy a $180,000 truck and your first-year income is only $60,000, bonus depreciation gives you a $120,000 NOL to carry forward. Section 179 would have capped you at $60,000 and left you waiting.

Used trucks qualify for bonus depreciation as long as they’re new to you. You can’t have previously used the specific vehicle in your trade or business, but buying a used Peterbilt from a dealer or another operator is fine. This was a change made by the TCJA; prior law limited bonus depreciation to new property only.

What if I bought my truck before January 20, 2025?

For trucks acquired after January 19, 2025, the full 100% rate applies with no phase-down, whenever they are placed in service. A truck acquired before January 20, 2025 stays on the old declining schedule: 40% if placed in service in 2025, 20% if placed in service in 2026. If you placed such a truck in service earlier, the reduced rate you claimed on your original return still applies to that specific asset, and the remaining undeducted basis continues to recover through regular MACRS over the rest of the recovery period. This is a backward-looking issue; any truck acquired today gets 100% bonus depreciation in full.

How does MACRS work without 179 or bonus depreciation?

If you don’t elect Section 179 and you’re not eligible for bonus depreciation (either because you opted out or the transitional rules apply), the truck’s cost is recovered through MACRS, the Modified Accelerated Cost Recovery System.

The recovery period depends on the type of vehicle. Over-the-road tractor units (the kind that haul a trailer under a fifth-wheel coupling) are 3-year property under MACRS Asset Class 00.26. Other trucks, including straight trucks, box trucks, and most vocational vehicles, are 5-year property.

MACRS uses the 200% declining balance method, which front-loads the deductions. For a 3-year asset under the half-year convention, the depreciation percentages are approximately 33.33%, 44.45%, 14.81%, and 7.41% over four tax years (the half-year convention spreads year one and the final year into partial periods). For a 5-year asset, the percentages are 20%, 32%, 19.2%, 11.52%, 11.52%, and 5.76% over six tax years.

The half-year convention assumes you placed the property in service at the midpoint of the year, regardless of the actual date. But if more than 40% of your total depreciable property for the year was placed in service in the last quarter (October through December), the mid-quarter convention kicks in instead. Under the mid-quarter convention, property placed in service in Q4 gets a much smaller first-year deduction. This penalizes late-year purchases when they’re heavily concentrated in the last quarter.

The mid-quarter convention is one reason to spread equipment purchases across the year, or to make sure your Q4 additions don’t exceed the 40% threshold.

Should an owner-operator use 179 or bonus on a tractor?

For most owner-operators buying a tractor, bonus is the simpler federal choice. It’s 100% for trucks acquired under a binding contract after January 19, 2025, it applies automatically, and it isn’t capped by taxable income. Section 179 can’t exceed your taxable income from active trades or businesses (W-2 wages count), with the excess carried forward.

A few other points can change the answer.

• A California individual filer gets no state bonus, and California’s Section 179 limit is $25,000 with a $200,000 phase-out threshold (2025 FTB 3885A), which doesn’t go far on a $180,000 truck. Other states need checking one by one.
• In an S corp, the 179 limits apply at the company and again for each shareholder, which can make bonus the easier path.
• You can combine them. Section 179 comes off first, then bonus applies to what’s left.

If bonus creates a loss, the excess business loss limit ($256,000, or $512,000 joint, for 2026) and the 80% NOL rule still apply.

What happens when I sell the truck?

When you sell a truck you’ve depreciated, IRC 1245 requires you to “recapture” the depreciation you previously claimed. Recapture means the gain on the sale, up to the amount of depreciation deducted, is taxed as ordinary income rather than as a capital gain.

If you bought a truck for $180,000, claimed $180,000 of depreciation (bringing the adjusted basis to $0), and then sold it for $45,000, the entire $45,000 is ordinary income under Section 1245. You don’t get capital gains rates on any portion that represents previously claimed depreciation.

This doesn’t mean you should avoid taking depreciation. The time value of money almost always favors taking the deduction now and paying recapture later. A $180,000 deduction in year one at a 35% rate saves $63,000 in cash today. If you sell the truck five years later for $45,000 and pay $15,750 in recapture tax (at the same 35% rate), you still came out $47,250 ahead, plus the investment value of having $63,000 in your pocket for five years. Depreciation isn’t free money, but it’s cheap money.

The recapture risk increases if your tax rate rises between the year of the deduction and the year of the sale. But for most owner-operators, rates don’t shift dramatically enough to offset the timing benefit.

If you trade in the truck rather than selling it outright, IRC 1031 does not apply. Like-kind exchange treatment was eliminated for personal property (including vehicles) by the TCJA in 2018. A trade-in is treated as a sale and a separate purchase: recapture on the old truck, fresh depreciation on the new one.

If you convert the truck from business use to personal use, you don’t trigger recapture at the time of conversion. But you stop claiming depreciation, and the recapture amount stays embedded in the truck’s basis. When you eventually sell or dispose of the truck, the recapture applies to the depreciation previously claimed during the business-use years.

When is the best time to buy a truck for tax purposes?

If you’re claiming 100% bonus depreciation, the timing within the year barely matters for federal purposes. A truck placed in service on January 2 and one placed in service on December 15 produce the same year-one deduction. The full cost is written off either way.

If you’re using MACRS without bonus (or if your state doesn’t conform to federal bonus depreciation), timing matters more. The half-year convention gives you half a year’s depreciation regardless of purchase date, so the federal number is the same whether you buy in February or September. The main risk is the mid-quarter convention: if more than 40% of your depreciable additions fall in Q4, the convention shifts, and Q4 purchases get a smaller first-year deduction.

The broader strategic question is matching income to deductions. If you’re having a high-income year and expect lower income next year, buying the truck this year captures the deduction when your marginal rate is highest. That’s the optimal result. If you’re having a low-income year, 100% bonus depreciation might create an NOL that carries forward at uncertain future rates. In that scenario, you might use Section 179 (which won’t create a loss) and let MACRS handle the remainder, or simply accept the NOL and carry it forward.

Financing terms also factor in. Dealership incentives, interest rates, and truck availability are business decisions that shouldn’t be bent entirely around the tax calendar. But all else being equal, buying a truck in a year when your income is high and your marginal rate is steep produces the best tax outcome.

What should I do next?

Depreciation is one piece of the owner-operator tax picture, but it’s often the single largest deduction on the return and the one most likely to be handled incorrectly. The choice between Section 179, bonus depreciation, and straight MACRS has real dollar consequences, and the right answer depends on your income level, your state’s conformity rules, and whether you’re operating as a sole proprietor or an S-corp.

These guides cover the related topics:

• Owner-operator deductions, the full list of Schedule C deductions for truckers
• Per diem meal deduction rules, how the 80% DOT meal rate works and what records you need
• Leasing vs buying a truck, when a lease makes more tax sense than ownership
• Entity structure for trucking, how the S-corp election interacts with depreciation and self-employment tax
• Retirement plans for owner-operators, using Solo 401(k) and SEP IRA to shelter income after depreciation

This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.