IRS red flags that trigger audits include underreporting income, taking disproportionately large deductions (especially for business, home office, or charitable donations), and failing to report foreign accounts or cryptocurrency transactions. High-income earners ($200k-$500k+) and those claiming 100% business vehicle usage also face higher scrutiny.
Not reporting all of your income is an easy-to-avoid red flag that can lead to an audit. Taking excessive business tax deductions and mixing business and personal expenses can lead to an audit. The IRS mostly audits tax returns of those earning more than $200,000 and corporations with more than $10 million in assets.
The overall odds of an IRS audit are low, about 4 out of every 1,000 returns. However, high-net-worth individuals are more likely to be targeted due to complex income sources, large deductions, and sophisticated financial structures.
You know the IRS might be investigating you through official mail (first contact), phone calls (often with automated messages to IRS.gov), or in-person visits, but signs of a criminal probe include contact with IRS Criminal Investigation (CI) agents, subpoenas to you or your bank, questions to your accountant/bank, unusual account activity (freezing/refusing transactions), or agents suddenly going silent after an audit. Key indicators are official IRS letters, contact from CI special agents, third-party inquiries, and formal summonses for records, signaling serious scrutiny beyond a simple audit.
Businesses that show losses are more likely to be audited, especially if the losses are recurring. The IRS might suspect that you must be making more money than you're reporting. Otherwise, why would you stay in business? Most likely to be audited are taxpayers reporting small business losses.
It's good to be specific, but there's a danger in words such as “everything,” “nothing,” “never,” or “always.” “You always” and “you never” can be fighting words that can distract readers into looking for exceptions to the rule rather than examining the real issue.
There are five potential threats to auditor independence: self-interest, self-review, advocacy, familiarity, and intimidation. Any lack of independence compromises the integrity of financial markets.
Here's a list of seven symptoms that call for attention.
If the deductions, losses, or credits on your return are disproportionately large compared with your income, the IRS may want to take a second look at your return. Taking a big loss from the sale of rental property or other investments can also spike the IRS's curiosity.
Ten Red Flags that Could Trigger an IRS Audit
The 5 Cs of audit (Criteria, Condition, Cause, Consequence, Corrective Action) are a framework for structuring clear, actionable audit findings, explaining what should be (Criteria), what is found (Condition), why it happened (Cause), what the impact is (Consequence/Effect), and how to fix it (Corrective Action/Recommendation) to drive organizational improvement and compliance.
Taxpayers whose tax returns have been flagged for possible IDT should receive one of the following letters: Letter 5071C, Potential Identity Theft during Original Processing with Online Option – Provides online and phone options and is issued most widely.
The IRS does not check every tax return. It does not check the majority of them, but the IRS implements methods that track certain factors that would result in a further examination or audit by them.
Evaluates the overall presentation, structure and content of the financial statements, including the disclosures, and whether the financial statements represent the underlying transactions and events in a manner that achieves fair presentation (i.e gives a true and fair view).
How to Wow Your Auditors
What Not to Say During an Audit?
Audit trends vary by taxpayer income. In recent years, IRS audited taxpayers with incomes below $25,000 and those with incomes of $500,000 or more at higher-than-average rates. But, audit rates have dropped for all income levels—with audit rates decreasing the most for taxpayers with incomes of $200,000 or more.
The IRS and its authorized private collection agencies will never ask a taxpayer to pay using any form of pre-paid card, store or online gift card. Taxpayers can review the IRS payments page at IRS.gov/payments for all legitimate ways to make a payment.
IRS Warning Signs of Federal Tax Evasion