IRS Audit Defense & Examination: Types, Triggers, and What to Do
Getting audited by the IRS can feel like a direct invasion of privacy. Discover the 3 types of IRS audits, common triggers, what examiners look for, and how to defend your return.
Quick Answer
IRS audits fall into three categories: correspondence audits (mail-based for specific lines), office audits (in-person at a local IRS office for detailed records), and field audits (comprehensive reviews conducted at your home or business). Preparing organized documentation, knowing your rights under the Taxpayer Bill of Rights, and having a licensed representative communicate on your behalf prevents audits from expanding into wider tax years.
Why was your return selected for audit?
Most taxpayers believe audits are personal vendettas. In reality, most returns are flagged by computer algorithms: the Discriminant Information Function (DIF) score evaluates your deductions against statistical norms for your income bracket.
Common triggers include high Schedule C business deductions relative to gross revenue, large cash donations without appraisal documentation, 1099 mismatches, cryptocurrency transactions, and claiming 100% business use of a personal passenger vehicle.
The three types of IRS audits
1. Correspondence Audit: Accounts for ~75% of all audits. The IRS mails a letter (e.g., CP2000 or Letter 566) asking for receipts or verification of 1 or 2 specific deductions (like childcare credits or college tuition).
2. Office Audit: You are summoned to a local IRS field office with specific financial records. The examiner interviews you directly regarding Schedule A or Schedule C items.
3. Field Audit: The most serious examination. An IRS Revenue Agent visits your home, place of business, or accountant's office to inspect books, physical inventory, and operations. Often involves high-net-worth individuals or small corporations.
The golden rule: Never attend an audit alone
Taxpayers who represent themselves at an office or field audit frequently volunteer harmful information out of nervous small talk. An offhand remark like 'Well, sometimes I use the business account for groceries when I'm busy' can trigger an immediate expansion into personal bank records and multiple tax years.
Under IRC §7521, you have the statutory right to be represented by a licensed Enrolled Agent, CPA, or Attorney through Form 2848 (Power of Attorney). Your representative attends in your place—you do not even have to speak to the IRS examiner.
Frequently Asked Questions
Answers to the questions taxpayers ask most about this topic.
How many years can the IRS go back in an audit?
The standard audit statute of limitations under IRC §6501 is 3 years from the date the return was filed. If there is a substantial understatement of income (greater than 25%), the IRS can go back 6 years. In cases of unfiled returns or fraudulent returns, there is no time limit.
What happens if I disagree with the audit findings?
You do not have to sign the examiner's report (Form 4549). You have 30 days to request a conference with the IRS Independent Office of Appeals. If appeals does not resolve it, you will receive a 90-day Notice of Deficiency allowing you to file a petition in U.S. Tax Court before paying the tax.
Can an audit lead to criminal charges?
Less than 1% of civil audits are referred to IRS Criminal Investigation (CI). A referral happens only if the auditor uncovers badges of intentional fraud, such as two sets of books, altered invoices, or hidden offshore accounts.