1. What a cost segregation study does
A building normally depreciates over 27.5 years (residential) or 39 years (commercial). A cost segregation study breaks the purchase price apart and reclassifies components like flooring, cabinetry, dedicated electrical, and land improvements into 5, 7, and 15-year property, so a large slice of the basis depreciates on much shorter schedules.
On the federal return, that reclassified property also qualifies for bonus depreciation, which restores a 100% first-year write-off for qualifying property acquired and placed in service after January 19, 2025. States set their own rules, which is where West Virginia comes in.
2. West Virginia and federal bonus depreciation
West Virginia fully conforms to IRC 168(k) bonus depreciation for both individual and corporate income tax, with no addback or modification. The state starts from federal AGI (individuals, W. Va. Code 11-21-9) and federal taxable income (corporations, 11-24-3) and has never decoupled from bonus. Its fixed-date conformity was updated in the 2026 session (SB 400 for personal income tax, SB 393 for corporate net income tax, both passed March 2026 and signed by Gov. Morrisey) to the IRC as amended through December 31, 2025, which captures OBBBA's permanent 100% bonus for property acquired after January 19, 2025. The update is expressly retroactive 'to the extent allowable under federal income tax law,' so 100% bonus flows through to tax year 2025 West Virginia returns as well as 2026 and beyond.
Worked example
A $1,000,000 building, with and without a study
Illustrative only. A residential rental purchased for $1,000,000 of building basis (land excluded), acquired and placed in service after January 19, 2025.
Building basis
$1,000,000
Reclassified to 5, 7, and 15-year property (25%)
$250,000
Federal first-year deduction at 100% bonus
$250,000
Year 1 on that $250,000 without a study (27.5-year straight line)
about $9,100
West Virginia conforms to federal bonus depreciation, so the state return mirrors the $250,000 first-year deduction.
Model your own numbers with the tax strategy projector.
3. Section 179 in West Virginia
West Virginia conforms to Section 179 in full through the same IRC conformity date (December 31, 2025), with no state-specific cap or recapture modification. That includes OBBBA's increased expensing limit of $2.5 million (with the $4 million phase-out threshold) for tax years beginning after 2024; the Governor's office specifically cited the increased small-business expensing up to $2.5 million as flowing through to state returns.
4. Does it still help in West Virginia?
Cost segregation works at full strength in West Virginia: both the reclassified 5/7/15-year MACRS lives AND 100% bonus depreciation on those reclassified components flow through to the state return with zero adjustment, so the state deduction mirrors the federal deduction dollar for dollar.
- •West Virginia has never decoupled from 168(k) bonus depreciation, putting it in the small minority of states with a full income tax and zero bonus addback.
- •Conformity is fixed-date but refreshed essentially every legislative session by an Executive-requested bill; the current date is December 31, 2025 (SB 393 corporate, SB 400 personal, both March 2026), expressly retroactive to the extent allowable under federal law.
- •Because the 2025 conformity bill (HB 2025) only reached the IRC as of December 31, 2024, West Virginia technically did not conform to OBBBA until March 2026; the retroactivity clause cured this for tax year 2025 returns filed during the 2026 season.
- •SB 392 (2026) cut personal income tax rates again: the 2026 bracket schedule tops out at 4.58% (down from 4.82% in 2025), with a revenue-trigger formula under W. Va. Code 11-21-4h producing further automatic cuts starting as early as tax year 2028 determinations.
- •Gov. Morrisey's office explicitly promoted the 2026 conformity bills as restoring 100% bonus depreciation and the $2.5 million Section 179 expensing cap at the state level.
- •Nonresident real estate sellers face West Virginia withholding at the top marginal rate (reduced to 4.58% by SB 392), relevant to out-of-state investors selling WV rentals.
- •West Virginia follows federal MACRS recovery periods (5/7/15/27.5/39-year) automatically since there are no state depreciation schedules or modifications at all.
5. The exit: recapture and timing
The accelerated deductions come back into view when you sell. Gain attributable to the 5, 7, and 15-year property is Section 1245 recapture, taxed at ordinary rates, and the straight-line depreciation on the building itself is unrecaptured Section 1250 gain, taxed at up to 25%. A study does not create that bill, it moves deductions forward, but the timing of the sale decides how much of the benefit you keep.
Two levers manage the exit. A 1031 exchange defers both flavors of recapture along with the rest of the gain, and simply holding the property lets the time value of the early deductions do its work; most owners want a 3 to 5 year horizon before a taxable sale for the math to stay comfortably positive. Model the exit before you commission the study, not after.