IRS Audit Red Flags: 15 Things That Trigger an Audit in 2025

Keep reading for details on why each one triggers audits — and what you can do about it.

Introduction

The fear of an IRS audit keeps millions of Americans up at night — and it’s understandable. The idea of the federal government scrutinizing your financial life is stressful, even if you’ve done nothing wrong. But understanding which IRS audit red flags actually trigger examinations in 2025 can help you file smarter, keep better records, and avoid the audit lottery altogether.

Here’s some perspective: the overall individual audit rate in recent years has been under 0.5%, meaning fewer than 1 in 200 returns gets examined. However, those odds change dramatically depending on what’s on your return. Certain factors — from your income level to specific deductions you claim — can increase your audit risk by 10x or more.

The IRS uses a sophisticated scoring system called the Discriminant Function (DIF) system to flag returns that are statistically likely to result in additional tax. Each return receives a DIF score based on how its deductions, credits, and income compare to similar returns. The higher your DIF score, the more likely your return is selected for audit.

In this guide, we’ll reveal the 15 biggest IRS audit red flags for 2025, explain why each one catches the IRS’s attention, and give you actionable advice for protecting yourself. And if you’ve already received an audit notice, our guide on what happens during an IRS audit will walk you through the process step by step.

1. High Income (Over $1 Million)

Income is the single biggest predictor of audit risk. The IRS disproportionately audits high-income taxpayers because the potential tax recovery is larger.

The data speaks for itself:

Income Level	Approximate Audit Rate
Under $25,000	~0.4% (mostly EITC-related)
$25,000 – $200,000	~0.2%
$200,000 – $500,000	~0.4%
$500,000 – $1,000,000	~0.7%
$1,000,000 – $5,000,000	~1.1%
$5,000,000 – $10,000,000	~2.0%
Over $10,000,000	~7.0%+

With increased IRS funding from the Inflation Reduction Act, audit rates for taxpayers earning over $400,000 are expected to increase significantly through 2025 and beyond. The IRS has hired thousands of new revenue agents specifically targeting high-income non-compliance.

How to protect yourself: Maintain meticulous records. If you earn over $500,000, consider having a tax professional prepare your return and keep organized documentation for every deduction and credit.

2. Unreported Income

The IRS receives copies of every W-2, 1099, K-1, and other information return sent to you. Its Automated Underreporter (AUR) system cross-references what third parties report with what you report on your tax return. Discrepancies are flagged automatically.

This isn’t really an “audit” in the traditional sense — it’s a computer match. But it’s the most common reason taxpayers hear from the IRS.

Common unreported income sources: – Freelance 1099-NEC income – Investment income (1099-INT, 1099-DIV, 1099-B) – Retirement distributions (1099-R) – Gambling winnings (W-2G) – Gig economy income (1099-K) — Note: payment apps and online marketplaces file Form 1099-K when your payments exceed $20,000 in more than 200 transactions, but the income is taxable even without a form – Rental income

How to protect yourself: Before filing, gather every information return you receive and make sure all income is reported on your return. If you received a 1099 that’s incorrect, contact the issuer to get it corrected rather than simply not reporting it.

3. Excessive Schedule C Deductions

Self-employed individuals who file Schedule C are among the most heavily audited taxpayers. The IRS knows that the self-employment tax system relies heavily on the honor system, and it uses DIF scoring to identify returns with deduction-to-income ratios that seem unusually high.

Red flag triggers: – Claiming deductions that exceed 50%+ of gross income – Reporting a net loss year after year (hobby loss rule under IRC § 183) – Large deductions for meals, travel, or entertainment – Deducting personal expenses as business expenses

According to IRS data, Schedule C filers with gross receipts under $25,000 and showing losses have an audit rate 5 to 10 times the national average.

How to protect yourself: Keep detailed records with receipts for every business expense. Maintain a separate business bank account. Document the business purpose of every deduction. If you regularly show losses, be prepared to demonstrate that you’re operating with a genuine profit motive.

4. Large Charitable Contributions

Charitable deductions are a legitimate and valuable tax benefit — but the IRS pays close attention when donations seem disproportionate to income. Claiming $50,000 in charitable contributions on a $100,000 income is going to raise eyebrows.

Key thresholds that increase scrutiny: – Cash donations exceeding $250 require written acknowledgment from the charity – Non-cash donations over $500 require Form 8283 – Non-cash donations over $5,000 generally require a qualified appraisal – Donations of property like artwork, real estate, or vehicles get extra attention

The IRS specifically watches for inflated valuations of non-cash donations — a common audit adjustment that can trigger accuracy-related penalties under IRC § 6662.

How to protect yourself: Keep detailed records — bank statements, receipts, acknowledgment letters. For non-cash donations, get independent appraisals when required. Never estimate or round up donation values.

5. Home Office Deduction

The home office deduction (IRC § 280A) has long been an audit magnet. While the deduction is perfectly legitimate for qualifying taxpayers, the IRS knows it’s frequently claimed improperly.

To qualify, you must use the space: – Regularly and exclusively for business (no dual-purpose rooms) – As your principal place of business, or as a place where you meet clients

Why it triggers audits: – Many taxpayers claim rooms that serve dual purposes (guest bedroom/office) – The deduction is easy to inflate by overstating square footage – It’s associated with other Schedule C deductions that increase overall scrutiny

How to protect yourself: Use the simplified method ($5 per square foot, up to 300 sq ft = $1,500 max) if your deduction is modest. If you use the regular method, take photos of your dedicated workspace, measure the square footage accurately, and ensure the space is used exclusively for business.

6. Claiming 100% Business Use of a Vehicle

Claiming that you use your car, truck, or SUV 100% for business is one of the fastest ways to attract IRS attention. Auditors know that virtually every taxpayer uses their vehicle for at least some personal trips — commuting, errands, vacations. A 100% business-use claim signals either dishonesty or ignorance of the rules.

IRS requirements for vehicle deductions: – You must maintain a contemporaneous mileage log (date, destination, business purpose, miles) – Personal commuting miles are never deductible – The log must be maintained throughout the year — reconstructed logs created at tax time are often rejected

How to protect yourself: Keep a mileage log app on your phone (MileIQ, Everlance, etc.) and record every business trip. Be honest about the business-use percentage. A claim of 75-85% business use with solid documentation is far stronger than 100% without records.

7. Reporting Rental Real Estate Losses

Rental property losses are another area of heightened IRS scrutiny. Under the passive activity rules of IRC § 469, rental losses are generally “passive” and can only offset passive income — not your W-2 wages or business income.

The exception: If your AGI is under $100,000 and you “actively participate” in rental management, you can deduct up to $25,000 in rental losses against non-passive income. This allowance phases out between $100,000 and $150,000 AGI.

Red flag triggers: – Claiming rental losses while having a high W-2 income – Reporting losses every year without ever showing rental profit – Claiming “real estate professional” status to unlock unlimited loss deductions (IRC § 469(c)(7)) — this is heavily audited

How to protect yourself: If you claim real estate professional status, document that you spend more than 750 hours per year in real estate activities AND more time in real estate than any other occupation. Keep detailed time logs. For standard rental deductions, maintain records of all expenses, property management activities, and tenant interactions.

8. Large Casualty and Theft Loss Deductions

After the Tax Cuts and Jobs Act (TCJA) of 2017, personal casualty and theft losses are only deductible if they result from a federally declared disaster (IRC § 165(h)(5)). Despite this restriction, some taxpayers still attempt to claim losses that don’t qualify or significantly overstate the damage.

What triggers scrutiny: – Casualty loss claims not connected to a FEMA-declared disaster – Loss amounts that seem inflated relative to the property value – Theft loss claims without police reports or documentation – Claims that appear to be personal misfortune repackaged as a qualified loss

How to protect yourself: Only claim losses from federally declared disasters. Document everything — photos, insurance claims, appraisals, FEMA declarations. Report insurance reimbursements accurately.

9. Running a Cash-Heavy Business

If you operate a business that deals heavily in cash — restaurants, bars, retail shops, salons, car washes, laundromats — expect higher IRS scrutiny. Cash businesses have historically been associated with underreported income because transactions are harder to trace.

IRS techniques for auditing cash businesses: – Bank deposit analysis: The IRS totals all bank deposits and compares them to reported income – Cash T analysis: Comparing known income sources to known living expenses – Markup analysis: Comparing your gross profit margins to industry averages – Net worth analysis: Tracking changes in assets and liabilities year-over-year

How to protect yourself: Deposit all cash receipts into your business bank account. Use point-of-sale systems that track transactions. Keep detailed daily records. Maintain separate personal and business accounts. If your reported income is consistent with industry norms, you’re less likely to be flagged.

10. Cryptocurrency Transactions

Cryptocurrency is one of the IRS’s top enforcement priorities. The IRS added a virtual currency question to Schedule 1 for tax year 2019 and moved it to the front page of Form 1040 for tax year 2020, and checking “No” when you actually had transactions is considered a false statement.

Why crypto triggers audits: – The IRS has issued John Doe summonses to exchanges like Coinbase and Kraken for user records – Many taxpayers fail to report crypto-to-crypto swaps as taxable events – DeFi transactions, NFT sales, and staking rewards are poorly understood and frequently misreported – The IRS has dedicated a team specifically to cryptocurrency compliance

Taxable crypto events include: – Selling crypto for fiat currency – Trading one crypto for another – Using crypto to buy goods or services – Receiving crypto as income, mining rewards, or airdrops

How to protect yourself: Use crypto tax software (CoinTracker, Koinly, etc.) to track all transactions. Report every taxable event. Keep records of your cost basis for all holdings. If you’ve failed to report crypto in prior years, consider a voluntary disclosure before the IRS contacts you.

11. Foreign Accounts and Assets (FBAR/FATCA)

International tax compliance is another top IRS enforcement priority. If you have foreign bank accounts, investments, or business interests, you’re on the IRS’s radar.

Reporting requirements: – FBAR (FinCEN Form 114): Required if your aggregate foreign account balances exceed $10,000 at any point during the year – FATCA (Form 8938): Required if foreign financial assets exceed $50,000 at year-end (or $75,000 at any time) for domestic filers; higher thresholds for overseas filers – Form 3520/3520-A: For transactions with or ownership of foreign trusts – Form 5471/8865: For ownership interests in foreign corporations/partnerships

Penalties for non-compliance are severe: – FBAR willful violation: Up to the greater of $100,000 (adjusted for inflation) or 50% of the account balance – FBAR non-willful violation: Up to $10,000 (adjusted for inflation) per report, not per account (Bittner v. United States, 2023) – FATCA failure: $10,000 per form, up to $60,000

How to protect yourself: Disclose all foreign accounts and assets. If you have past non-compliance, consider entering the IRS Streamlined Filing Compliance Procedures or making a voluntary disclosure. For more on how the IRS discovers unreported foreign accounts, see our guide on the IRS audit statute of limitations for FBAR.

12. Early Retirement Account Distributions

Taking money out of IRAs, 401(k)s, or other retirement accounts before age 59½ triggers a 10% early withdrawal penalty (IRC § 72(t)) on top of ordinary income tax. The IRS watches closely for:

• Distributions reported on 1099-R that aren’t included on the tax return
• Rollovers that weren’t completed within the 60-day window
• Claiming exceptions to the 10% penalty without proper documentation
• Substantially equal periodic payment (SEPP/72(t)) distributions that are modified before the required period ends

How to protect yourself: Report all retirement distributions accurately. If you qualify for an exception to the 10% penalty (disability, first-time home purchase, medical expenses, etc.), document the exception thoroughly and file Form 5329.

13. Earned Income Tax Credit (EITC) Claims

The EITC is a refundable credit worth up to $7,830 (2024 tax year) for low-to-moderate income workers with qualifying children. It’s also one of the most frequently audited credits due to historically high error rates — the IRS estimates an EITC improper payment rate of approximately 25-30%.

Common EITC audit triggers: – Claiming children who don’t meet the relationship, age, or residency tests – Filing as Head of Household when the living arrangement doesn’t qualify – Understating income to fall within EITC income limits – Self-employment income that appears inflated to maximize the credit

How to protect yourself: Ensure every qualifying child meets all four tests: relationship, age, residency (living with you for more than half the year), and joint return test. Keep records that prove your children lived with you — school records, medical records, lease agreements.

14. Round Numbers on Deductions

This might seem trivial, but IRS computers flag returns with suspiciously round numbers. Claiming exactly $5,000 in business travel, $3,000 in supplies, and $2,000 in meals signals that you’re estimating rather than tracking actual expenses.

Real expenses rarely come out to perfectly round numbers. A travel deduction of $4,847 looks legitimate. A travel deduction of $5,000 looks made up.

How to protect yourself: Always use actual amounts from receipts and records. Never estimate or round to the nearest hundred or thousand. If you’ve been estimating, start keeping detailed records now to support accurate figures going forward.

15. Filing an Amended Return With Large Changes

Amended returns (Form 1040-X) receive higher scrutiny than original returns, especially when they result in a significant refund or a large reduction in income. The IRS reviews every amended return manually — there’s no automated processing like with original returns.

Red flags on amended returns: – Claiming large new deductions or credits not on the original return – Changing filing status (e.g., from Married Filing Jointly to Married Filing Separately) – Reducing reported income significantly – Filing multiple amended returns for the same tax year

How to protect yourself: Only amend when there’s a legitimate reason. Include a clear explanation of what changed and why. Attach supporting documentation for every adjustment. If the changes are substantial, consider having a tax professional prepare the amended return.

How to Reduce Your Audit Risk in 2025

Beyond avoiding specific red flags, these general practices will lower your overall audit risk:

• 1. File electronically— E-filed returns have lower error rates than paper returns
• 2. Double-check math and data entry— Simple errors trigger correspondence audits
• 3. Report all income— Even if you didn’t receive a 1099, report the income
• 4. Keep records for at least 3 years(6 years is safer) — See our guide on the IRS audit statute of limitations
• 5. Use a qualified tax professional— Professionally prepared returns have lower audit rates
• 6. Don’t be afraid of legitimate deductions— The goal isn’t to avoid deductions but to document them properly
• 7. Respond promptly to IRS correspondence— Ignoring letters escalates problems. Check our guides on CP504 and LT11

What to Do If You’re Selected for an Audit

If the worst happens and you receive an audit notice, don’t panic. Read our comprehensive guide on what happens during an IRS audit and consider these immediate steps:

• 1. Read the notice carefully— Determine the audit type and scope
• 2. Don’t ignore it— Failure to respond results in automatic adjustments against you
• 3. Gather your records— Start organizing documentation for the items under review
• 4. Consider professional representation— An Enrolled Agent or Tax Resolution Specialist can represent you and often achieves better outcomes. Learn 10 expert tips for surviving an audit.
• 5. Know your rights— The Taxpayer Bill of Rights (IRC § 7803(a)(3)) protects you throughout the process

Frequently Asked Questions

What are the chances of being audited in 2025?

The overall individual audit rate has been historically low — under 0.5% in recent years. However, audit rates vary dramatically by income level, return complexity, and specific items claimed. With the IRS receiving additional funding under the Inflation Reduction Act, the agency has hired thousands of new enforcement personnel and audit rates are expected to increase, particularly for taxpayers earning over $400,000. The IRS has stated it will not increase audit rates for taxpayers earning under $400,000 above historical levels. Still, every return is screened by the DIF computer system regardless of income.

Does the IRS audit the same person twice?

Yes, the IRS can and does audit the same taxpayer multiple times, though there are some protections. Under IRC § 7605(b), the IRS generally cannot examine the same items for the same tax year more than once. However, the IRS can audit different tax years or different issues on a return it previously examined. If you were audited recently and your return was accepted with no changes, and the IRS proposes an audit for a subsequent year with the same issues, you can invoke the repetitive audit protection by contacting the auditor’s supervisor. This doesn’t guarantee the audit will stop, but it may limit its scope.

Can I avoid an audit by not claiming deductions?

Technically, not claiming deductions reduces your DIF score — but that’s a terrible strategy. You’d be paying more in taxes than you legally owe just to avoid an audit you might never get. The IRS audit rate is low enough that the statistical cost of an audit is far less than the tax savings from legitimate deductions. The better approach is to claim every deduction you’re entitled to and document them thoroughly. If you’re ever audited and have proper documentation, the audit should confirm your return with no changes. Don’t leave money on the table out of fear.

What happens if I ignore an IRS audit notice?

Ignoring an audit notice is one of the worst things you can do. If you don’t respond, the IRS will proceed with the audit without your input and make adjustments based solely on the information available to them — which almost always results in a larger tax bill. The IRS will then issue a Notice of Deficiency (90-day letter), and if you still don’t respond, the assessment becomes final. This can lead to wage garnishments, bank levies, tax liens, and other enforced collection actions. Always respond to audit notices, even if you need to request more time.

How far back can the IRS audit me?

The standard IRS audit statute of limitations is 3 years from the date you filed your return (or the due date, whichever is later) under IRC § 6501. However, this extends to 6 years if you omit more than 25% of your gross income, and there’s no time limit for fraud or if you never filed a return. The IRS can also go back 6 years for FBAR violations. In practice, most audits focus on returns filed within the last 2-3 years. Keep records for at least 6 years to be safe.

Does having a tax professional prepare my return prevent audits?

Having a tax professional doesn’t make you audit-proof, but it does help in several ways. Professionally prepared returns tend to have fewer errors, proper documentation, and positions that are defensible under the tax code. If you are audited, having a professional who knows your situation and can represent you before the IRS (Enrolled Agents, CPAs, and attorneys have representation rights under Circular 230) significantly improves outcomes. Some tax professionals also carry audit protection insurance that covers the cost of representation if you’re audited.

Don’t Face an IRS Audit Alone

Whether you’re trying to minimize your audit risk or you’ve already received a notice, professional guidance makes all the difference. Our experienced tax professionals have defended thousands of taxpayers through IRS audits and know exactly how to protect your rights and your wallet.

Need help? Call Global Gate Tax Relief at 1-877-800-8180 for a free consultation. Our team of tax professionals has helped thousands of Americans resolve their IRS problems.