Comprehensive cost segregation analysis for real estate investors. A cost segregation study reclassifies portions of a building's basis from 27.5- or 39-year real property (slow depreciation) into 5-year personal property, 7-year office furniture, and 15-year land improvements (fast depreciation, often eligible for § 168(k) bonus depreciation). This tool models the reclassification based on property-type industry benchmarks, separates federal and state treatment (only 8 states conform to § 168(k) bonus), applies the mid-month convention based on the month placed in service, computes the first-year deduction, projects multi-year tax benefits, calculates study-cost ROI, and shows the § 1245 / § 1250 recapture exposure at sale.
This tool is informational only. The actual reclassification percentage depends on a qualified engineering-and-tax study performed by a cost segregation specialist; published benchmarks are general industry averages and any specific property may produce materially different results. The IRS's "Cost Segregation Audit Techniques Guide" (2022) governs the standards for a defensible study. Specific facts and circumstances may produce a different result. Engage qualified counsel and a qualified cost segregation engineer before relying on the projections produced by this tool.
Enter the property's acquisition basics. The month placed in service drives the mid-month convention factor for the 27.5- or 39-year building shell.
Select the property type. Each type has a typical range of cost-segregated reclassification percentages observed in industry studies. The default reclass % is set to the midpoint; adjust below based on the actual engineering study.
Used to convert the deduction into a dollar value of tax benefit.
Cost segregation studies range from $4,000 (small residential) to $25,000+ (large commercial). For property placed in service in prior years, a look-back study with § 481(a) catch-up recovers missed depreciation in the year of the change.
When enabled, applies the firm's proprietary methodology to the cost segregation analysis. The result is presented below alongside the standard calculation so you can see the additional benefit. The underlying technique is reserved to the firm's engagement and is not disclosed in this tool.
Cost segregation is most powerful when combined with the tangible property regulations under § 263(a) and the related safe harbors.
When a structural component of a building is replaced (e.g., a roof, HVAC system, windows), the taxpayer may elect to recognize a loss on the abandoned component equal to its remaining adjusted basis. The election must be made on a timely-filed return (including extensions) for the year of disposition. A cost segregation study identifies the basis of the disposed component, enabling the election. The election is annual and item-by-item.
Recurring maintenance activities that the taxpayer reasonably expects to perform more than once during the property's class life are deductible currently rather than capitalized. For building systems, the class life is 10 years (so the activity must reasonably be expected to recur within 10 years). Common qualifying activities include painting, minor HVAC servicing, and elevator maintenance.
Taxpayers may elect to deduct items costing $5,000 or less per invoice/item (for taxpayers with an applicable financial statement) or $2,500 or less (without an AFS) if the taxpayer has a written capitalization policy in place at the start of the year. The election is made annually on Form 4562 with an attachment. Critical for STR investors purchasing furniture, fixtures, and equipment in bulk.
Distinguishing "betterment" (capitalize) from "ordinary maintenance" (deduct) is a major audit issue. A cost segregation study performed in conjunction with a major remodel allocates the cost between capitalized improvements and deductible repairs. For STR property, the distinction is especially valuable because turnover-related painting, flooring patches, and fixture replacements often qualify as deductible repairs rather than capitalized improvements.
Cost segregation accelerates deductions but also accelerates the recapture exposure at sale. The reclassified portion is § 1245 personal property, which on sale recaptures depreciation as ordinary income at the taxpayer's marginal rate, not at the maximum 25% § 1250 rate. The trade-off is favorable when:
For taxpayers who plan a short hold or who expect their marginal rate to rise sharply, the benefit of cost segregation may be smaller than a static first-year-deduction analysis would suggest. Use the rental real estate tax strategy analyzer for a complete after-tax NPV that includes recapture.
The tool allocates the reclassified portion across the standard MACRS shorter-life categories: 5-year property (carpet, decorative lighting, removable appliances, kitchen cabinets in residential STR, decorative millwork) under the 200% declining balance method, half-year convention; 7-year property (office furniture, fixtures) under the 200% declining balance method, half-year convention; 15-year property (land improvements: paving, fencing, landscaping, exterior lighting, signage) under the 150% declining balance method, half-year convention. The remaining building shell is depreciated as 27.5-year residential real property or 39-year nonresidential real property, both under the straight-line method with the mid-month convention. The mid-month convention treats property as placed in service at the midpoint of the month in which it is actually placed in service; the Year 1 factor is (12 − month + 0.5) / 12 × (1 / recovery years).
Under Reg. § 1.168(d)-1, the mid-quarter convention applies when more than 40% of the aggregate depreciable basis of personal property (5-, 7-, and 15-year property) is placed in service in the last quarter of the tax year. The convention shifts the Year 1 depreciation factor based on the quarter of placement, often producing a smaller Year 1 deduction than the half-year default. However, § 168(k) bonus depreciation is taken first, before regular MACRS, and the bonused portion is removed from the mid-quarter test. When bonus is 100%, the entire reclassified amount is bonused, leaving no basis subject to MACRS — the mid-quarter convention has no remaining property to apply to. Mid-quarter matters in three scenarios: (i) the taxpayer elects out of bonus under § 168(k)(7); (ii) bonus is less than 100% (e.g., the 2023–2025 phasedown); (iii) the property is not bonus-eligible (e.g., used property acquired from a related party). In all other cases, with 100% bonus, the month placed in service does not affect the reclassified portion's deduction.
Of the 41 states with an income tax, only 8 conform to § 168(k): Alabama, Colorado, Kansas, Louisiana, Missouri, Montana, Oklahoma, and Utah. The remaining 33 income-tax states "decouple" from bonus depreciation, requiring taxpayers to add back the federal bonus deduction and re-compute state depreciation using regular MACRS (no bonus) on the reclassified portion. The 9 no-income-tax states (AK, FL, NV, NH, SD, TN, TX, WA, WY) produce no state-level analysis. For non-conforming states, the State Year 1 deduction is materially smaller than the Federal Year 1 deduction — often the difference between a $300K federal Year 1 deduction and a $30K state Year 1 deduction on the same study. The reduction in state benefit can shift the study ROI analysis for high-bracket investors in NY, CA, NJ, and other non-conforming jurisdictions.
Property placed in service after September 27, 2017 and before January 1, 2023: 100%. Calendar 2023: 80%. Calendar 2024: 60%. Calendar 2025 before January 20: 40%. Calendar 2025 on or after January 20 (per the One Big Beautiful Bill Act, signed July 4, 2025): 100% and permanent. The tool defaults to 100% reflecting the current OBBBA-restored rate; for prior years, adjust the bonus rate input accordingly.
For residential 27.5-year real property, the Year 1 mid-month factors are: Jan 3.485%, Feb 3.182%, Mar 2.879%, Apr 2.576%, May 2.273%, Jun 1.970%, Jul 1.667%, Aug 1.364%, Sep 1.061%, Oct 0.758%, Nov 0.455%, Dec 0.152%. For nonresidential 39-year real property: Jan 2.461%, Feb 2.247%, Mar 2.033%, Apr 1.819%, May 1.605%, Jun 1.391%, Jul 1.177%, Aug 0.963%, Sep 0.749%, Oct 0.535%, Nov 0.321%, Dec 0.107%.
The reclassification ranges shown for each property type are industry typicals drawn from published studies. Actual percentages vary significantly with the specific property's age, condition, layout, mechanical systems, fit-out, and use. Residential STR 20–30%; Residential LTR 15–25%; Office 25–35%; Retail 30–40%; Industrial 35–45%; Hospitality 25–35%; Medical 35–50%; Self-storage 35–45%; Restaurant 35–45%.
For property already placed in service in a prior tax year, a look-back cost segregation study reclassifies portions of basis after the fact. The taxpayer files Form 3115 (Application for Change in Accounting Method) under designated change number (DCN) 7 (automatic procedure for impermissible-to-permissible depreciation method change). The § 481(a) adjustment recovers the cumulative missed depreciation in the year of the change, deducted in full without amending prior returns. There is no statute of limitations risk on the § 481(a) catch-up.
The tool produces approximate estimates. The actual reclassification depends on the engineering-and-tax study, which requires a qualified specialist's site inspection. State conformity to bonus depreciation is modeled; state non-conformity to MACRS recovery periods themselves, separate state-specific depreciation methods (e.g., the PA pre-2023 personal income tax non-conformity to MACRS), § 199A qualified business income deduction limitations, § 461(l) excess business loss limitation, and § 163(j) interest deduction limitation are not modeled here. Consult qualified counsel before relying on these projections.