#cost-segregation
Engineering-based studies that reclassify building components into shorter MACRS lives to accelerate depreciation deductions
A practical guide to Section 469(c)(7) Real Estate Professional Status — the 750-hour and more-than-half tests, the spousal rule, material participation and the grouping election, common audit failures, and how 100% bonus depreciation in 2026 makes REPS worth the documentation cost.
A cost segregation study uses engineering-based analysis to move 20–45% of a building's basis from 27.5- or 39-year straight-line into 5, 7, and 15-year MACRS classes. Combined with the 100% bonus depreciation permanently restored by the One Big Beautiful Bill Act for property placed in service after January 19, 2025, real estate investors can convert a routine $91,000 first-year deduction into roughly $766,000 — provided they clear IRC §469 passive activity loss limits via real estate professional status, the short-term rental rule, or passive income offsets.
How short-term rentals sit outside the Section 469 passive loss rules, what the seven-day average and material participation tests actually require, and how a six-figure W-2 earner can use cost segregation and 100% bonus depreciation to legally offset wage income.
Form 3115 lets U.S. taxpayers change accounting methods and use a Section 481(a) adjustment to recover missed deductions or correct multi-year errors on a single current-year return, without amending prior years.
Section 1031 lets real estate investors defer capital gains and depreciation recapture by swapping investment properties, but only when the 45-day identification window, 180-day closing deadline, qualified intermediary rules, and post-TCJA like-kind requirements are followed exactly.
A cost segregation study reclassifies a building's components into shorter MACRS lives, unlocking the 100% bonus depreciation permanently restored by the One Big Beautiful Bill Act of July 2025. On a $1M residential rental, that swings first-year tax savings from roughly $10,700 to roughly $90,600—provided the investor clears IRC §469 passive activity loss limits.
