Section 179 & Bonus Depreciation for Vehicles in 2026
When you put a vehicle in service for business, the IRS gives you two powerful first-year write-off options — Section 179 expensing and bonus depreciation. Together they can let a small business deduct a large chunk of a $65,000 SUV or pickup in year one. But the rules around vehicle weight, business-use percentage, and annual caps are dense. This guide walks through the 2026 numbers so you can run the calculator above with confidence and have an informed conversation with your CPA.
The core idea: instead of spreading a $50,000 truck deduction across 2026 through 2031, you take a large chunk — sometimes all of it — on your 2026 return. That front-loads the tax benefit, frees up cash, and rewards businesses that invest in equipment. The trade-off is complexity. Get the GVWR class wrong or let business use slip below 50%, and the IRS can recapture the deduction years later with interest and penalties. The authoritative source for all depreciation rules is IRS Publication 946, which the calculator above is based on.
What is Section 179?
Section 179 of the Internal Revenue Code lets a business treat the purchase of qualifying equipment — including certain business vehicles — as an immediate expense rather than a capitalized asset depreciated over five or six years. The deduction flows through to whichever tax return matches your business entity: Schedule C for sole props and single-member LLCs, Form 1065 for partnerships, Form 1120 or 1120-S for corporations. You elect it line-by-line on Form 4562, and you can elect any amount up to the annual limit — including zero if you'd rather save the deduction for a higher-income year.
For 2026, the overall Section 179 limit is $1,220,000, and the spending phase-out begins at $3,050,000 of total equipment placed in service during the year. Above the phase-out threshold, every dollar of equipment reduces your Section 179 limit dollar-for-dollar, and the deduction disappears entirely at $4,270,000 of purchases.
The SUV cap and why it exists
Congress added a special restriction for "sport utility vehicles" between 6,001 and 14,000 pounds GVWR: a $30,800 Section 179 cap for 2026. The reason is simple — without it, every consultant and real-estate agent would buy a $90,000 luxury SUV and write the whole thing off in year one. The cap forces owners of heavy SUVs and pickups to expense $30,800 up front and depreciate the rest (or take bonus depreciation on the remainder). Genuine heavy vehicles above 14,000 GVWR — dump trucks, semis, box trucks, bucket trucks — are exempt from the SUV cap and can use the full $1,220,000 Section 179 limit.
Bonus depreciation phase-down schedule
The 2017 TCJA set bonus depreciation at 100% through 2022, then stepped it down 20 points per year. The schedule looks like this: 60% in 2024, 50% in 2025, 40% in 2026 (the current year), 20% in 2027, and 0% in 2028 unless Congress extends it. For 2026 you can deduct 40% of the remaining basis (after Section 179) of qualifying business property in year one. Bonus depreciation applies automatically unless you elect out — and unlike Section 179, it has no overall dollar cap and no business-use percentage floor.
Section 179 vs bonus depreciation: what's the difference?
The two are similar in effect but different in mechanics. Section 179 is optional and you pick the dollar amount — any figure up to the limit, or less if it suits your tax situation. Bonus depreciation is automatic at 40% for 2026; it applies to the full basis of eligible property unless you elect out, and the election-out is by asset class, not property-by-property. The ordering rule matters: you apply Section 179 first (up to the SUV cap or overall limit), then apply 40% bonus to whatever basis remains, then depreciate the rest under normal MACRS rules. Most tax software handles this automatically, but understanding the sequence helps you spot errors.
Vehicle weight classes and the 6,000 lb GVWR line
The GVWR threshold is the single most important number in vehicle depreciation. A vehicle rated at 6,000 lb or less is treated as a passenger automobile and falls under the luxury auto caps — roughly $20,160 in year one with bonus depreciation. Cross the 6,001 lb line and the vehicle becomes a "heavy SUV" eligible for the $30,800 Section 179 cap plus 40% bonus on the remainder. Above 14,000 lb GVWR, the SUV cap disappears entirely and the full $1,220,000 Section 179 limit applies. Always confirm the GVWR on the door jamb sticker before relying on this treatment, and verify your vehicle's weight rating with our Truck GVWR / GCWR Calculator.
The 50% business-use rule
Section 179 requires that the vehicle be used more than 50% for business. Buy a $50,000 truck at 80% business use and the qualifying cost is $40,000. If you claimed Section 179 and then business use drops to 50% or below in a later year, you must recapture the excess deduction as ordinary income on that year's return. Bonus depreciation has a similar but less strict recapture framework. For mixed-use vehicles, keep a mileage log — the IRS expects contemporaneous records, and apps like Stride or MileIQ are acceptable. The calculator's "business use %" field directly scales the qualifying cost.
Mid-year timing: placed in service by December 31
Both Section 179 and bonus depreciation require that the vehicle be placed in service — not merely purchased or ordered — before the end of the tax year. A truck delivered December 15 and put into route service December 20 qualifies for 2026. A truck ordered in November but not delivered until January 5, 2027 goes on the 2027 return. There is no half-year convention exception for these deductions; it is all or nothing on the placed-in-service date. Dealers sometimes push year-end deals with loose delivery promises — get the date in writing.
State conformity: California and the holdouts
Many states do not conform to federal bonus depreciation. California does not allow bonus depreciation at all and decoupled from federal Section 179 years ago — California's Section 179 limit is only $25,000 with its own smaller SUV cap. Other non-conforming or partially conforming states include Arkansas, Hawaii, Mississippi, and parts of New York. You may owe state tax on depreciation you wrote off federally, producing a state-level addition modification. Your federal return and state return will tell different stories; budget for the state bill. If you drive for business, also check our IRS Standard Mileage Deduction Calculator to compare the actual-expense method against the simpler cents-per-mile approach.
The bottom line
For a typical 2026 purchase — say, a $65,000 heavy-duty pickup at 80% business use — the calculator shows roughly $30,800 of Section 179, about $8,480 of 40% bonus depreciation on the remainder, and a year-1 deduction around $39,280. At a 24% marginal rate that is roughly $9,427 in federal tax savings. The remaining basis depreciates over five years under MACRS. Run the numbers for your own vehicle and rate, then confirm with a CPA before filing — vehicle depreciation is one of the most audit-prone areas of small-business tax returns. For the full cost-of-ownership picture on a commercial truck, pair this with our Commercial Truck Operating Cost Calculator.