Section 179 and Bonus Depreciation for Contractors: The Equipment Expensing Rules That Affect Every Capital Decision

Construction companies routinely purchase expensive depreciable assets — pickup trucks, excavators, cranes, skid steers, trailers, tools, office equipment, technology. Federal tax law provides two mechanisms for accelerating the deduction of these costs: Section 179 expensing and bonus depreciation. Both let contractors deduct substantial portions of equipment cost in the year of purchase rather than spreading the cost over years through regular depreciation.

Understanding how Section 179 and bonus depreciation work — and how they interact with each other and with regular MACRS depreciation — enables tax-efficient structuring of equipment purchases. This post covers the fundamentals with emphasis on construction-specific issues.

Section 179 Basics

Section 179 allows immediate expensing:

Section 179 is elective. Contractor chooses to expense rather than depreciate. Annual limit and phase-out thresholds mean Section 179 benefits smaller operations more than very large ones. Contractors purchasing more than phase-out threshold get reduced 179 benefit.

Bonus Depreciation

Bonus depreciation is separate mechanism:

Bonus depreciation complements Section 179. Bonus percentage applies to property placed in service; remainder depreciated normally. Bonus percentage phase-down under current law affects timing decisions — accelerating purchases to capture higher bonus may make sense in some situations.

Interaction Between Them

Section 179 and bonus interact:

Combining Section 179 and bonus depreciation can deduct substantial portion of equipment cost in year of purchase. For contractors with taxable income, the mechanisms substantially reduce tax bills on equipment-heavy years.

Vehicle Limitations

Vehicles have specific rules:

Vehicle rules create specific planning opportunities. Heavy pickup trucks used for business often qualify for full Section 179 / bonus depreciation. Passenger vehicles face luxury auto limits that cap annual deduction regardless of 179 or bonus. Construction-use pickup trucks typically fare well.

State Tax Considerations

State treatment varies:

State decoupling creates book-state differences. A federal deduction not allowed at state level increases state taxable income. Multi-state contractors face different rules in different states. State-specific planning matters.

Timing Considerations

Timing affects benefit:

Year-end tax planning often involves equipment purchases. Business with strong income year may purchase equipment to offset. Business with weak year may defer purchases. Coordination with tax advisor critical.

Financed Purchases

Financed equipment still qualifies:

Financed purchases create tax benefit exceeding cash outflow. A $100K truck financed creates $100K deduction (if eligible) but only partial-year payments. This is beneficial but requires cash flow management — tax savings don't cover loan payments in later years.

Recapture on Disposition

Recapture affects disposition:

Equipment sold later produces taxable gain to extent of depreciation. Contractor who expensed $100K truck with 179/bonus, then sold for $30K five years later, has $30K recapture. Planning should consider full lifecycle including disposition.

Bottom Line

Section 179 and bonus depreciation accelerate tax deduction of equipment purchases. Section 179 requires taxable income; bonus depreciation can create loss. Current law phases down bonus percentage. Vehicles have specific rules — heavy pickups typically qualify well, passenger vehicles face luxury auto limits. State conformity varies. Financed purchases still qualify. Recapture applies on disposition. For equipment-heavy contractors, proper use of these mechanisms substantially affects tax position. Year-end planning often involves equipment timing. Coordination with tax advisor ensures proper structuring. Contractors ignoring these mechanisms overpay tax; contractors using them well manage tax burden on equipment investments. Equipment depreciation is one of the largest tax planning levers for construction companies.