Tax Act Restores 100% Bonus Depreciation, Solidifying Full Write-Off for Heavy Business Vehicles

WASHINGTON — A recent federal tax act has permanently restored 100% bonus depreciation for qualifying property, a move that solidifies a powerful tax-planning strategy for business owners purchasing heavy vehicles. The provision, part of legislation colloquially named the “One Big Beautiful Bill Act,” applies to assets acquired and placed in service after January 19, 2025. When combined with Section 179 of the tax code, this change allows businesses to potentially deduct the entire purchase price of a qualifying new or used SUV or truck in the first year.

The strategy, often dubbed the “G-Wagon Loophole” on social media, is not new, but the permanent restoration of 100% bonus depreciation provides new certainty for long-term capital planning. Previously, bonus depreciation had been scheduled to phase down, dropping to 60% in 2024 and decreasing further in subsequent years. The new law reverses this trend, re-establishing a significant incentive for capital investment.

To qualify for this accelerated depreciation, a vehicle must have a Gross Vehicle Weight Rating (GVWR) of over 6,000 pounds. This specification, found on a sticker inside the driver's-side door jamb, includes many popular large SUVs, pickup trucks, and cargo vans used by small and mid-sized companies in sectors like construction, real estate, and professional services.

The tax benefit is realized through a two-step process. First, a business can use the Section 179 deduction to immediately expense a portion of the vehicle's cost. For the 2026 tax year, the specific Section 179 deduction for heavy SUVs is capped at $32,000, according to one analysis. Second, the 100% bonus depreciation under §168(k) can be applied to the remaining cost basis of the vehicle. For a $100,000 vehicle used exclusively for business, a company could take the maximum Section 179 deduction and then apply bonus depreciation to the rest, resulting in a full $100,000 deduction in the year the vehicle is placed in service.

Crucially, the Internal Revenue Service imposes strict requirements for claiming these deductions. The vehicle must be used more than 50% for qualified business purposes. If business use is, for example, 80%, then only 80% of the vehicle's cost is eligible for the deductions. The IRS requires meticulous record-keeping to substantiate business use, including a detailed mileage log that tracks business versus personal travel.

According to IRS guidance, business owners can generally choose between deducting the actual costs of using their vehicle or taking the standard mileage rate. The accelerated depreciation method falls under the “actual expenses” category, which also allows for the deduction of costs like fuel, insurance, repairs, and registration fees, proportional to the business-use percentage. The total deduction under Section 179 cannot exceed the taxpayer's aggregate net business income for the year.

To claim the deduction, taxpayers must file Form 4562, “Depreciation and Amortization,” with their annual tax return. The vehicle must be purchased and officially placed in service—meaning titled, insured, and actively used for business—by the last day of the tax year, which for most businesses is December 31. Simply ordering a vehicle is not sufficient.

This tax treatment offers a significant cash-flow advantage compared to standard depreciation, which spreads the deduction over several years. By accelerating the entire deduction into the first year, a business can substantially lower its taxable income, freeing up capital for other investments, debt reduction, or operational needs.

In our experience, while the allure of a six-figure, first-year deduction is powerful, business owners must recognize that the IRS is acutely aware of how this provision can be misused. We have seen audits triggered by sloppy record-keeping where business use was not rigorously documented from day one. This is not simply about buying a car; it is about implementing a compliant asset management strategy. The deduction is a powerful tool for managing taxable income, but business owners must treat the documentation with the same seriousness as the purchase itself. This accelerated depreciation also has future consequences, such as potential tax liability from depreciation recapture if the vehicle is sold for a gain later. Our firm's tax preparation and compliance services focus on ensuring clients not only claim every deduction they are entitled to but also have the bulletproof records to defend it. For guidance on navigating these complex vehicle depreciation rules, business owners can contact C&S Finance Group LLC at csfinancegroup.com.

Looking ahead, business owners considering a vehicle purchase should consult with tax professionals to model the financial impact and ensure compliance with all documentation requirements. While the 100% bonus depreciation has been made permanent, other related figures, such as Section 179 limits, are still subject to annual inflation adjustments, requiring ongoing attention from taxpayers planning capital expenditures.