Cost Segregation Report: What's Inside & How to Read It

By Chirag Gandhi · Short Term Rental Taxes & active STR owner Reviewed by an independent CPA firm · Read bio & methodology →

Guide 16 of 35Cluster guide6 min readOctober 2026

Quick answer

A cost segregation report is the written document that shows how your building's cost was split into 5-, 7-, 15-, and 27.5- or 39-year property. A quality report includes an executive summary, property description, methodology, legal analysis, detailed asset schedules, photos, and a reconciliation to your total cost. Your CPA uses it to set up depreciation and support it if the IRS asks.

This content is not tax or financial advice for you. Please talk with a CPA to find what's right for your situation.

The main sections of a quality report

1. Executive summary

A one- or two-page overview showing the total cost basis, how much went into each asset class, and the estimated first-year deduction. This is what most people read first.

2. Property description

Address, property type, square footage, date placed in service, and how the building is used. Use matters because it can change an asset's tax life.

3. Methodology

How the study was done: site visit or virtual tour, cost sources used, and which approach (for example, detailed engineering cost estimate). This section shows the IRS the work is reliable.

4. Legal and technical analysis

The tax rules and court cases that support each classification. It explains why, for example, a dedicated electrical circuit for kitchen equipment is personal property rather than part of the building.

5. Asset detail schedules

The heart of the report. Every component is listed with a description, quantity, unit cost, total cost, asset class, and recovery period.

6. Photos and drawings

Pictures of components and, when available, floor plans or site plans. These support the classifications.

7. Reconciliation

A table proving that all the allocated amounts add up exactly to your cost basis, including how indirect costs (like closing costs or permits) were spread.

8. Depreciation schedule

Many reports include a year-by-year depreciation table your CPA can import directly. For look-back studies, it may show the Form 3115 catch-up amount.

9. Preparer credentials

Names and qualifications of the engineers or specialists who did the work.

A sample summary table

Here's what a simple executive summary might look like for a $1.2 million apartment building with $240,000 of land:

Asset class	Recovery period	Amount	Share of depreciable basis
Personal property	5 years	$163,200	17%
Land improvements	15 years	$86,400	9%
Building	27.5 years	$710,400	74%
Total depreciable basis	—	$960,000	100%
Land (not depreciable)	—	$240,000	—

What to check before you hand it to your CPA

Does the total match your cost basis? Compare it to your closing statement.
Is land excluded? Land should never appear in a depreciable asset class.
Are the dates right? The placed-in-service date drives bonus depreciation eligibility.
Are the preparers named? Unnamed reports are weaker in an audit.
Does it explain the method? A report with numbers but no method is a red flag.

How long should a report be?

It depends on the property, but a quality report for a mid-size building often runs dozens of pages. A two-page summary with no backup is a warning sign.

Frequently asked questions

Do I file the report with my tax return?

No. You keep it in your records. Your return reflects its results.

How long should I keep it?

As long as you own the property, plus at least three years after the return for the year you sell.

Can my CPA change the numbers in the report?

Your CPA decides how to apply it, such as whether to take bonus depreciation, but shouldn't change the allocations without support.

See what your property may qualify for

Run our 2-minute STR Qualification Quiz or model your Low / Mid / High cost segregation range.

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