IRS audits are typically triggered by inconsistencies, such as unreported income (mismatched 1099s/W-2s), excessive deductions relative to income, or mathematical errors. Other major red flags include high-income levels, running a cash-intensive business, claiming the home office deduction, or frequent losses on a Schedule C.
Ten Red Flags that Could Trigger an IRS Audit
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.
You're a Very High Earner. While most taxpayers' chance of audit is less than 1%, the odds increase once you earn $500,000 or more in taxable income. Those reporting more than $10 million have the highest risk of a tax audit.
Many people worry about IRS audits. But the chances of being audited are actually very low for most individuals. Recent IRS data shows the IRS examined 0.40% of individual returns filed and 0.66% of corporation returns filed. Most of the IRS's focus is on large businesses and high-income earners.
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.
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.
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.
Here's a list of seven symptoms that call for attention.
The Unreported Income DIF (UIDIF) score rates the return for the potential of unreported income. IRS personnel screen the highest-scoring returns, selecting some for audit and identifying the items on these returns that are most likely to need review.
What happens during an audit? Internal audit conducts assurance audits through a five-phase process which includes selection, planning, conducting fieldwork, reporting results, and following up on corrective action plans.
Let's explore the IRS audit triggers to keep you in the clear.
Audit evidence is critical for verifying the accuracy of financial statements and supporting auditors' opinions. Different types of audit evidence include physical examination, documentation, observations, inquiries, confirmations, analytical procedures, and reperformance.
There are three main types of audit risk—inherent risk, control risk, and detection risk—along with a fourth related concept, sampling risk, which can affect the reliability of audit evidence.
Red Flags are indicators or warning signs that suggest potential issues, weaknesses, or irregularities in an organization's financial processes, compliance, or operations.
Here's what happens if you ignore an office audit:
You may have avoided the meeting, but you'll pay for it later in taxes, penalties, and interest. The IRS will change your return, send a 90-day letter, and eventually start collecting on your tax bill. You'll also waive your appeal rights within the IRS.
How to Wow Your Auditors
The IRS $600 rule refers to a change in reporting requirements for third-party payment apps (like Venmo, PayPal) for taxable income from goods and services, where platforms must send a Form 1099-K if you receive over $600 in a year, intended to capture gig economy/side hustle income, though delays and phased implementation have adjusted the timeline, with current rules for 2024 using a higher threshold ($5,000) before fully phasing to $600 for future years, but remember all taxable income, regardless of form, must always be reported.
The IRS generally audits a larger share of high-income taxpayers than those with lower incomes, as illustrated in Figure 1. However, those who claim the Earned Income Tax Credit (EITC)—who typically have low incomes—are much more likely to face an audit than all but the highest-income taxpayers.
The 2-year rule for audit is quite simple. If a company meets two or more of the above criteria for two years in a row, then it must have a statutory audit. Conversely, a firm that currently has to be audited can't qualify for an audit exemption until it fails to meet at least two over the criteria over two years.