09/07/2026
Before the One Big Beautiful Bill Act, bonus depreciation was phasing out — 40% in 2025, 20% in 2026, gone by 2027. Businesses were racing a calendar. Now, for qualified property acquired and placed in service after January 19, 2025, the rate is 100% with no scheduled sunset.
What that unlocks, particularly for property owners:
A building itself is 27.5- or 39-year property and gets no bonus. But a cost segregation study reclassifies components — electrical, specialized HVAC, flooring, site improvements — into 5-, 7- and 15-year lives that do qualify. At 100% bonus, those reclassified dollars come off in year one instead of over decades.
Qualified improvement property gets the same treatment. A $400,000 interior renovation of commercial space is fully deductible in the year placed in service rather than spread across 15 years.
Section 179 still has a role, especially for roofs, HVAC and security systems on nonresidential property. For 2026 the cap is $2.56M with a $4.09M phase-out.
Three caveats worth knowing before you get excited: bonus depreciation can create a net operating loss and Section 179 can't; states don't all conform; and accelerated depreciation gets recaptured when you sell.
Acceleration isn't a bigger deduction. It's the same deduction, earlier — which only helps if this year's rate beats the rate in the years you'd otherwise claim it.