What Are the Different Types of IRS Audits?
The word “audit” tends to conjure a fairly specific and intimidating image, but the reality covers a much wider range, from a routine letter in the mail to a more involved in-person review.
The short answer
IRS audits generally fall into three categories: correspondence audits handled entirely by mail, office audits that require an in-person meeting at a local IRS office, and field audits where an examiner visits the filer’s home or business. Correspondence audits are by far the most common and typically address a single, narrow issue. Office and field audits tend to involve more complex returns or larger discrepancies.
Correspondence audits
A correspondence audit is conducted entirely through the mail and usually focuses on one specific item, such as a claimed deduction or a credit that doesn’t match third-party reporting. The notice explains what’s being questioned and what documentation is needed to resolve it. Because these are narrow in scope, they tend to be the fastest to resolve, and understanding how an IRS audit typically starts is especially useful here, since correspondence audits often begin with a very specific, identifiable trigger.
Office audits
An office audit requires the filer, or a representative, to appear in person at a local IRS office to go through documentation with an examiner. These typically cover more than a single line item and can involve several aspects of a return, though they’re still generally more limited in scope than a field audit. Bringing organized, complete records — the kind detailed in guidance on what records to bring to an audit — tends to make this type move more efficiently.
Field audits
A field audit is the most comprehensive type, involving an examiner visiting a home or place of business to review records directly and sometimes ask about the operation itself. These are more common for business returns or for individual returns involving more complex financial situations, such as significant self-employment income. Because of their scope, field audits generally take considerably longer to resolve than the other two types.
Comparing the three at a glance
- Correspondence audits. Conducted by mail, narrow in scope, generally the quickest to resolve.
- Office audits. Conducted in person at an IRS office, moderate in scope, involving direct document review.
- Field audits. Conducted at the filer’s home or business, broadest in scope, generally the most time-consuming.
Why the distinction matters
Knowing which type of audit a notice describes helps set realistic expectations for how much time and documentation will be involved. A correspondence audit asking about one deduction is a very different undertaking than a field audit examining a full year of business records, even though both technically fall under the same word. How long each type of examination tends to take is covered separately in guidance on how long an IRS audit usually takes, since the type is one of the biggest factors in that timeline.
The takeaway
The three types of IRS audits differ mainly in scope and format — mail, office, or in-person visit — and knowing which one applies is the first step in responding appropriately. Reading the notice carefully to identify the type, rather than assuming the most intensive scenario by default, is a useful starting point for anyone who receives one.