The IRS Audit Techniques Guide in Plain Terms

The IRS has published an audit techniques guide about cost segregation. Audit techniques guides are training and reference materials for examiners. They are not law, and they do not bind taxpayers, but they show how examiners are taught to think about a topic. Understanding the general themes can help you evaluate studies. The guide has been revised over time, so check the current edition through the IRS website or your preparer rather than relying on this summary.

What the guide is and is not

It is a set of examination guidance describing how a study might be reviewed, what makes a study more or less reliable, and how classification issues arise. It is not a rulebook that defines exactly what must appear in every study, and it does not approve any provider or method. Court decisions and Treasury regulations, not the guide, are the source of legal rules.

Themes about study quality

The guide has generally described a detailed, engineering-based approach as more reliable than rough estimates, and it has described elements that support quality. Broadly, and in general terms, those elements include:

• A description of the methodology used.
• Involvement of people with relevant qualifications and experience.
• A review of the property in person, where appropriate.
• Reliance on actual cost records where available, or documented estimating methods where not.
• A clear reconciliation to the total cost.
• Documentation of the reasoning for classification.

Compare these with What an Engineering-Based Study Typically Includes and What a Cost Segregation Report Should Contain.

Themes about classification

The guide discusses the distinctions between property that is part of a building and property that is separately depreciable, and it refers to case law on what makes an item structural. It also discusses land improvements versus building components. These are technical areas where facts and judgment matter, which is why documentation of reasoning helps.

Themes about specific issues

Across the guidance, examiners are pointed to issues such as how costs were allocated, whether estimation methods were reasonable, treatment of indirect costs, and the handling of items removed when property is replaced. For owners, the practical takeaway is that a study should address these topics on its face.

What it means for you

• Use the guide's themes as a checklist for asking provider questions. See How to Vet a Cost Segregation Provider.
• Ask your preparer whether they are familiar with the guide and how they use it.
• Do not treat a provider's statement that a study "follows IRS guidelines" as proof of quality. Ask which elements it includes and ask for a sample.

Limits of relying on any guide

Guidance can be revised. Courts can decide cases in ways that shift the analysis. Different examiners can reach different views. The law that applies to your property depends on when it was placed in service and other facts. For these reasons, the guide is a source of orientation rather than a guarantee.

How this connects to software-only approaches

Some lighter approaches do not include the elements the guide has associated with quality, such as a site visit. That does not mean such a study will be rejected, and this site does not claim that. It means the support is different, and you should weigh that. See Engineering-Based Versus Software-Only Studies.

Keeping up to date

Ask your preparer or provider to point you to the current version and to any recent court decisions relevant to your property type. See Audit Defense and Documentation for Cost Segregation for recordkeeping.

A reading tip for the primary source

If you decide to read the guide itself, read it with a purpose. Look first at the sections that describe how examiners are told to evaluate the quality of a study. Then read the sections on the classification of specific items that appear in your property. Do not try to memorize it. Note questions to ask your provider and your preparer. Because the guide has been revised, confirm you have the current version and note its date in your file.

How the guide relates to court decisions

Court decisions on classification of components shape the law that examiners apply. The guide summarizes some of that law, but it is not a substitute for reading the cases or having your advisor do so. If your property has unusual features, ask whether any decisions bear on them.

Practical takeaways

The guide supports a few plain habits: document your method, use qualified people, reconcile costs, explain classification, and keep records. Those habits are worth adopting whether or not you ever expect to see an examiner.

Questions the guide suggests to ask yourself

Was the study prepared by someone with relevant qualifications? Does it describe how the property was inspected and how costs were derived? Do the classifications make sense given the use of the property? Can each cost be traced to a source? Can I explain the total? Working through such questions before you file is a practical way to use the themes without reading every page of a lengthy document.

Next steps

Use the guide's themes to review any proposal. Then read Red Flags in Cost Segregation Study Proposals to see common warning signs and Cost Segregation Decision Checklist for the broader decision.