Every fourth quarter, the same question surfaces in dealership conversations across the country: is this the year to buy? For fleet managers and owner-operators, the answer often depends on Section 179 and bonus depreciation under Section 168(k)— two provisions of the tax code that, despite their outsized financial impact, remain widely misunderstood.
Dealers who can speak to these provisions with precision become a genuine resource to buyers during one of the most consequential purchasing decisions a business will make all year. Here’s everything you should know ahead of the deadline.
Section 179 vs. Bonus Depreciation: How They Differ
Section 179 and bonus depreciation both allow businesses to deduct the cost of qualifying equipment in the year it’s placed in service, rather than spreading that deduction across a multi-year depreciation schedule. But the mechanics diverge in ways that matter.
Section 179 is an election, meaning businesses choose which assets to expense, up to an annual dollar limit. For 2025, that limit is $2,560,000, and it begins phasing out dollar-for-dollar once total qualifying purchases exceed $4,090,000, disappearing entirely at $6,650,000. Section 179 is also capped by taxable income: it can reduce a tax bill to zero, but it cannot create a loss.
Bonus depreciation, by contrast, applies automatically to remaining eligible basis unless a business opts out for an entire class of property. It carries no dollar cap, and unlike Section 179, it can create a net operating loss. Starting 2026, bonus depreciation sits at 100% for qualifying property acquired and placed in service after January 19, 2025, a rate made permanent under the One Big Beautiful Bill Act.
How the Two Provisions Stack
For most buyers, these provisions aren’t an either/or choice. A business typically elects Section 179 first on priority assets, then lets bonus depreciation absorb whatever basis remains. Consider a business placing $4.3 million of qualifying equipment in service in 2025: because that exceeds the $4,090,000 phase-out threshold by $210,000, the available Section 179 deduction shrinks by that same amount — from $2,560,000 down to $2,350,000. The remaining $1,950,000 in basis then flows to bonus depreciation, which has no cap to worry about.
This stacking mechanism is often the piece buyers understand least and where a well-prepared sales team adds the most value. Knowing how to walk a customer through a real, numbers-based scenario, rather than a general description of “tax savings,” is what separates a transactional conversation from a genuinely advisory one.
What This Means for Your Sales Conversations
Because both new and used work-trucks qualify under Section 179 and Section 168(k), dealers have room to guide buyers toward the purchase that fits their actual financial picture. That might mean structuring a purchase to land under the phase-out threshold, or timing a placed-in-service date to align with a buyer’s fiscal year.
None of this replaces a tax advisor, and dealers should be careful not to present themselves as one. But understanding the difference between an election and an automatic deduction, or between a capped benefit and an uncapped one, allows sales teams to ask sharper questions and flag the right issues before a buyer’s accountant does.
Preparing for a Season Built on Precision, Not Pressure
Equip your team with FAQ sheets that go beyond the basics, including the phase-out math, the interaction between the two provisions, and the taxable-income limitation on Section 179 are the details that build credibility with sophisticated buyers. Year-end tax season rewards dealers who can meet informed buyers with informed answers, without relying on urgency. In a purchase this consequential, precision is what earns trust and trust is what brings buyers back next season.
