Section 179 Tax Deduction
Section 179 on GMC Trucks & Vans in Maine
If you run a business in Southern Maine and you buy a qualifying GMC truck or van and put it to work before December 31, 2026, you can generally write off up to 100% of the purchase price on your 2026 return instead of depreciating it over six years. Section 179 covers the first $2,560,000 of equipment; 100% bonus depreciation covers what Section 179 caps. The catch is the calendar: the truck has to be delivered and in service by December 31 — a signed buyer's order on December 30 doesn't count.
How Section 179 actually works in 2026
The short version: Section 179 of the IRS tax code lets a business deduct the full purchase price of qualifying equipment — including work trucks and vans — in the year it's placed in service, rather than spreading the deduction across the vehicle's depreciable life. For tax year 2026 the ceiling is $2,560,000, and it phases out dollar-for-dollar once total qualifying purchases pass $4,090,000 (gone entirely at $6,650,000). Where Section 179 is capped — most notably the $32,000 limit on heavy SUVs — 100% bonus depreciation generally picks up the remaining basis, so the first-year write-off can still reach the full purchase price.
The four tests a vehicle has to pass
- Business use over 50%. The vehicle has to be used more than half the time for business in the year you place it in service. Exactly 50% does not qualify. Your deduction is proportional to the business-use percentage.
- Placed in service by December 31, 2026. Delivered, titled, and actually working for the business. This is the one that bites people in the last week of December.
- Titled to the business and used in a trade or business you materially participate in.
- Weight and body style. GVWR (gross vehicle weight rating — the number on the driver's door jamb sticker) and, for pickups, cargo bed length determine which bucket the vehicle lands in. See the table below.
Two other limits worth knowing before you sign
- Section 179 can't exceed your business's taxable income. If the deduction would push you into a loss, the excess carries forward. Bonus depreciation has no such limit — it can create a loss. This is exactly why the two get used together.
- Recapture. If business use drops to 50% or below in a later year, part of the deduction gets added back to income. Keep a mileage log.
Why Section 179 matters more on a Maine return
Maine does not follow federal bonus depreciation. Maine Revenue Services continues to decouple from it and requires that depreciation be claimed over the asset's normal life instead.
For tax year 2025, Maine conformed to the federal Section 179 rules under Public Law 119-21. That combination matters: on your federal return, Section 179 and bonus depreciation do similar work — but on the Maine return, the bonus half of that strategy gets added back while Section 179 expensing does not.
Translation for a Maine business owner: how your CPA splits the write-off between Section 179 and bonus depreciation can change your state tax bill even when the federal number is identical. It's worth a phone call to your accountant before you pick the truck, not after.
Maine's conformity is set legislatively and can change year to year. Confirm the 2026 treatment with your tax advisor before filing.
Questions to bring to your CPA
- Should we take Section 179, bonus, or a mix on this unit?
- What does the Maine add-back look like either way?
- Does the Maine Capital Investment Credit apply to us this year?
- What's our projected taxable income — enough to absorb a full Section 179 deduction?
- Are we better off placing a second unit in service in January instead?
Which GMC vehicles qualify, and for how much
Three buckets, decided by GVWR and — for pickups — whether the cargo bed measures at least six feet inside. Verify the GVWR on the door jamb sticker of the specific unit before you count on a category; it changes by cab, drivetrain, and package.
| Category | GMC models at Weirs | First-year write-off |
|---|---|---|
| Full expensing Over 6,000 lbs GVWR, cargo bed 6 ft or longer, cargo vans, chassis cabs |
Sierra 1500 with the 6'6" standard box or 8' long box · Sierra 2500HD · Sierra 3500HD (SRW and DRW) · Sierra 3500HD Chassis Cab · Savana Cargo Van · Savana Cutaway · Savana Passenger (10+ seats only) | Up to 100% of the purchase price, no per-vehicle cap |
| Heavy SUV / short-bed cap 6,001–14,000 lbs GVWR, passenger body or bed under 6 ft |
Sierra 1500 with the 5'8" short box (including Denali and AT4) · Yukon and Yukon XL · Acadia · Canyon · Hummer EV Pickup and SUV · Sierra EV · Savana Passenger under 10 seats | $32,000 under Section 179, plus 100% bonus depreciation on the balance — which in most cases still gets you to the full purchase price in year one |
| Light vehicle limit 6,000 lbs GVWR or less |
Terrain · Canyon in configurations rated at or under 6,000 lbs | Capped at $20,300 of first-year depreciation for 2026 (with bonus), under the Section 280F luxury auto limits |
The six-foot bed rule, because it surprises people: a crew cab Sierra 1500 with the 5'8" box is treated as an SUV and hits the $32,000 Section 179 cap. The same truck with the 6'6" box escapes the cap entirely. The bed is measured inside, bulkhead to closed tailgate. If you're choosing between two trucks on the lot and the write-off matters, the box length is the spec to check.
What it looks like on a real truck
Sierra 2500HD work truck — $68,000
Over 6,000 lbs GVWR with a long box, so there's no per-vehicle cap.
| Purchase price | $68,000 |
| Section 179 deduction | $68,000 |
| Estimated first-year tax savings at a 24% rate | $16,320 |
Yukon Denali — $86,000
Heavy SUV, so Section 179 stops at $32,000 — and bonus depreciation covers the rest.
| Section 179 (capped) | $32,000 |
| 100% bonus depreciation on the remaining basis | $54,000 |
| Total first-year deduction | $86,000 |
Illustration only, assuming 100% business use. Your rate, your entity type, your state add-backs, and your taxable income all change the answer. These figures are not a promise of any tax benefit.
December 31 is a delivery deadline, not a paperwork deadline
At Weirs GMC we see the same thing every December: somebody calls the week of Christmas wanting a chassis cab with a dump body on it, and there isn't a body shop in New England that can turn that around in five days.
If the truck needs an upfit
A chassis cab isn't in service until the body is on it and it's working. Plow, dump body, service body, rack, liftgate — order by mid-November to be safe. After that you're gambling on an upfitter's schedule.
If the truck is on the lot
Stock units can be delivered quickly, but financing, titling, insurance, and registration all have to land before year end — and the last week of December is short on business days in Maine. Two weeks of runway is comfortable.
Section 179 questions we get at the dealership
Does a used truck qualify for Section 179?
Yes. The vehicle has to be new to you, not new off the truck. A pre-owned Sierra 2500HD bought from Weirs and placed in service in your business before December 31 qualifies the same way a new one does, as long as you didn't acquire it from a related party.
Can I finance the truck and still take the deduction?
Yes. Section 179 is based on the purchase price of the vehicle, not on how much cash you put down. A financed or qualifying-lease-to-own truck placed in service in 2026 is generally deductible in full for 2026 even if you've made only one payment. That's the part most business owners find hardest to believe.
What if my upfit isn't finished by December 31?
Then the vehicle most likely isn't placed in service for 2026, and the deduction moves to 2027. "Placed in service" means ready and available for its assigned function in your business. A chassis cab sitting at the upfitter waiting on a dump body doesn't meet that test. Order upfit units by mid-November.
How much can I deduct on a GMC Yukon or Acadia?
Section 179 is capped at $32,000 for 2026 on vehicles between 6,001 and 14,000 lbs GVWR that are built primarily to carry passengers. But bonus depreciation has no such cap, so 100% bonus depreciation generally covers the remaining basis and the first-year write-off can still reach the full purchase price at 100% business use.
Does a Sierra 1500 qualify for the full deduction?
It depends on the box. A Sierra 1500 with the 6'6" standard box or the 8' long box has a cargo bed of at least six feet and is exempt from the $32,000 SUV cap, so it can be fully expensed. The 5'8" short box — common on crew cabs, including Denali and AT4 — falls under the cap, with bonus depreciation covering the balance.
Do I have to use the truck 100% for business?
No, but you need more than 50% business use in the year you place it in service, and your deduction is reduced to the business-use percentage. A $70,000 truck used 80% for business gives you a $56,000 basis to work with. Keep a mileage log — if business use later drops to 50% or below, some of the deduction is recaptured as income.
Does Maine follow the federal Section 179 rules?
Maine conformed to the federal Section 179 changes for tax year 2025, but Maine continues to decouple from federal bonus depreciation and requires depreciation over the asset's normal life instead. That makes the Section 179 portion of your write-off more valuable on a Maine return than the bonus portion. Confirm the current year's treatment with your tax advisor.
Is there a limit on how much my business can deduct in total?
For 2026, Section 179 tops out at $2,560,000, and it starts phasing out dollar-for-dollar once you place more than $4,090,000 of qualifying property in service during the year, disappearing at $6,650,000. Section 179 also can't exceed your business's taxable income — the excess carries forward. For the vast majority of Southern Maine businesses buying one or two trucks, none of these ceilings come into play.
Family-owned since 1961. Southern Maine's GMC truck store.
We've been writing work trucks for contractors, landscapers, plumbers, and excavators from Portland to Kennebunk to Biddeford for over sixty years. Tell us what the truck has to do and when you need it, and we'll tell you honestly whether we can have it working for you before December 31.
Weirs GMC, 1513 Portland Rd, Arundel, ME 04046. This page is general information, not tax advice, and Weirs Motor Sales is not a tax advisor. Eligibility, limits, and the treatment of any particular vehicle depend on your business, your entity type, your business-use percentage, and federal and Maine law, all of which can change. Figures reflect IRS inflation adjustments for tax year 2026 (Rev. Proc. 2025-32 and Rev. Proc. 2026-15) and the depreciation provisions of Public Law 119-21. Consult your own tax advisor before making a purchase decision. Last updated September 2026.