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What is Cost Segregation? A Simple Guide for Rental Property Investors

Jan 2025 1 min read

Last reviewed: 2026-02-26

Quick Summary

What is Cost Segregation? A Simple Guide for Rental Property Investors. Learn how to accelerate depreciation and save on taxes.

Tax law changes over time. RentalWriteOff provides bonus depreciation applicability analysis in every report.

Cost segregation is an IRS-recognized tax strategy that reclassifies parts of a building into shorter depreciation lives. For residential rentals, this can shift deductions earlier compared with standard 27.5-year treatment.

The core concept

Instead of treating the entire building as one long-life asset, a study identifies components that may fall into shorter classes, commonly 5, 7, and 15 years.

Common residential classes

  • 5-year property: often includes certain appliances, carpet, and removable fixtures
  • 7-year property: selected specialty items depending on facts and use
  • 15-year property: many land improvements such as driveways, fencing, and landscaping
  • 27.5-year property: building structure and core components

Why investors and CPAs use it

Reclassification can increase early-year depreciation and improve cash flow timing. When bonus depreciation rules apply to eligible classes, first-year impact may be larger.

What makes a defensible study

  • Property-specific inputs and documentation
  • Clear asset classification logic
  • Supportable basis allocation and schedules
  • Final quality check before delivery

Next step

If you are a property owner, start with our instant estimate. If you are a CPA firm, review our white-label platform.