How Far Back Does the IRS Go for an Audit? Know Everything Now

How Far Back Does the IRS Go for an Audit? Discover IRS audit deadlines, exceptions, and how many years the IRS can review.

Many taxpayers feel anxious when they hear the word “audit.” One of the most common questions people ask is how far back does the IRS go for an audit. Knowing the answer can help you stay prepared, protect your records, and reduce unnecessary stress.

The IRS follows specific time limits, known as statutes of limitations, when reviewing tax returns. However, these limits vary depending on the situation. In this guide, we break down the rules, exceptions, and best practices so you understand exactly what to expect.

Understanding IRS Audit Time Limits

An IRS audit is a formal review of your tax return to verify that income, deductions, and credits are reported correctly. The IRS cannot audit returns forever—but in certain situations, it can go back much further than most taxpayers realize.

In general, how far back the IRS goes for an audit depends on what it finds in your return.

IRS Audit Timeframes at a Glance

Situation	How Far Back the IRS Can Audit
Accurate return, no major issues	3 years
Income underreported by 25%+	6 years
Fraud suspected	Unlimited
No tax return filed	Unlimited
Foreign income/assets not reported	6+ years

This table highlights why accurate reporting and proper recordkeeping are essential.

The Standard 3-Year IRS Audit Rule

For most taxpayers, the IRS follows a three-year rule. This means the IRS can audit tax returns filed within the last three years.

Important points:

• The three-year clock starts from the date the return was filed
• Early filings are counted from the official tax due date
• Applies when no significant errors are present

Example

If you filed your 2021 tax return on April 15, 2022, the IRS generally has until April 15, 2025, to audit that return.

For the majority of people asking how far back does the IRS go for an audit, this three-year window is the most common answer.

The 6-Year Rule for Underreported Income

The IRS can extend the audit period to six years if it determines that you underreported your gross income by 25% or more.

This often applies to:

• Self-employed individuals
• Small business owners
• Freelancers and contractors
• Investment or rental income earners

Example

If your return reported $80,000 in income but should have shown $110,000 or more, the IRS may audit up to six years back.

This rule exists to give the IRS more time to uncover substantial income omissions.

No Time Limit for Fraud or Unfiled Returns

In certain cases, there is no statute of limitations at all.

The IRS can audit unlimited years if:

• You committed tax fraud
• You never filed a tax return

Tax fraud involves intentional actions such as hiding income, falsifying records, or claiming deductions you know are false. If fraud is proven, the IRS can review any tax year, no matter how old.

Likewise, if you fail to file a return, the IRS can assess taxes at any time.

What Triggers an IRS Audit?

Understanding common audit triggers can help lower your risk.

Common IRS Audit Triggers:

• Large or unusual deductions
• Major income changes from year to year
• Cash-based businesses
• Self-employment income
• Foreign bank accounts or assets
• Missing or mismatched forms (W-2s, 1099s)

Being audited does not automatically mean wrongdoing—it often means the IRS wants clarification.

How Long Should You Keep Tax Records?

Since the answer to how far back does the IRS go for an audit varies, keeping records long enough is crucial.

IRS Record Retention Guidelines:

• 3 years for standard tax returns
• 6 years if income may be underreported
• 7 years for loss or bad debt claims
• Indefinitely for unfiled returns or fraud concerns

Keep documents such as receipts, invoices, bank statements, and proof of income. Digital records are acceptable if readable and complete.

What Happens During an IRS Audit?

IRS audits generally fall into three categories:

1. Correspondence Audit – Conducted by mail; most common
2. Office Audit – In-person meeting at an IRS office
3. Field Audit – IRS visits your home or business; most serious

The IRS will notify you by mail and specify which years are under review.

Can the IRS Extend the Audit Period?

Yes. The IRS may ask you to sign a form agreeing to extend the statute of limitations. This usually happens when an audit is complex and nearing the deadline.

You are not required to agree, but refusing may lead the IRS to issue an assessment based on available information.

How to Reduce Your Audit Risk

While no one can guarantee avoiding an audit, you can lower your chances by:

• Reporting all income accurately
• Keeping clear and organized records
• Avoiding unsupported deductions
• Filing on time
• Working with a qualified tax professional

Preparation is the best defense.

Frequently Asked Questions (FAQ)

Final Thoughts

So, how far back does the IRS go for an audit? For most taxpayers, the answer is three years, but that window can expand to six years or even unlimited time in serious cases. Understanding these rules allows you to stay compliant, keep the right records, and respond confidently if the IRS ever comes calling.