Bozeman cost segregation: CPA reference worksheet

For accountants, EAs, and tax preparers evaluating a Bozeman cost segregation study before signing off on the deduction. Engine methodology, state conformity, audit-defense documentation.

1. State conformity for Montana

Montana partially decouples from federal §168(k) bonus depreciation. MT historically required addbacks for federal bonus depreciation with recovery over the regular MACRS schedule for state purposes. For 2025+ acquisitions under OBBBA's 100% federal bonus, the MT-side timing mismatch is modest at the 5.9% top rate. The federal §168(k) acceleration is unaffected; only the MT Schedule reconciliation is the variable.

Decoupling note: Montana has periodically modified bonus depreciation conformity. Verify current-year treatment with your CPA.

2. MACRS classification (Rev. Proc. 87-56 + IRS Pub. 946)

The engine assigns MACRS class lives by component category, derived from Rev. Proc. 87-56 asset class tables. Summary:

Component categoryRecovery periodIRS asset class (typical)
Personal property: FF&E, decorative finishes, certain electrical (kitchen plugs), carpet5-yearAsset class 57.0 (distributive trades) or building-specific
Personal property: office equipment, certain agricultural7-yearAsset class 00.11 (office furniture and equipment)
Land improvements: paving, landscaping, fencing, site lighting, hardscape15-yearAsset class 00.3 (land improvements)
Residential rental structure27.5-year SL§168(e)(2)(A)
Nonresidential real property (office, retail, industrial)39-year SL§168(e)(2)(B)

3. Bonus depreciation (current law)

OBBBA (One Big Beautiful Bill Act, signed July 2025) permanently restored 100% bonus depreciation under §168(k) for property placed in service in 2025 and later. Historical: 80% (2023), 60% (2024), 100% (2025 onward). Bonus applies to all assets with MACRS recovery periods of 20 years or less, so all 5, 7, and 15-year components reclassified by the study are bonus-eligible.

4. Engine methodology summary

For a Bozeman property, the Cost Seg Smart engine:

  1. Determines land allocation from county assessor records (if available and reliable) or from a statistical metro → state → national fallback. Premium land floor applies when reconciliation rf_raw exceeds 2.0.
  2. Applies RSMeans 2024 base $/SF costs to component categories, scaled by the geographic factor for Bozeman's metro tier.
  3. Applies BLS PPI to adjust RSMeans 2024 dollars to the property's acquisition-date dollars.
  4. Applies STR FF&E uplift if the property is a short-term rental (engine treats this differently from long-term rentals).
  5. Reconciles component-bottom-up sum against the depreciable basis to produce the final MACRS allocation.
  6. Runs 16-check QC validation (PASS / REVIEW / FAIL) with compound-OK downgrade logic before emitting the final study.

Full methodology at costsegsmart.com/methodology.

5. Audit defense documentation

Each Cost Seg Smart study includes written audit defense documentation as part of the deliverable. The package contains:

For complex audits requiring expert testimony, Cost Seg Smart engineering review is available on retainer.

6. CPA channel

Cost Seg Smart operates a CPA partner portal for white-label studies, branded client links, and partner margin tracking. If you're advising Bozeman-area clients regularly, email [email protected].