Quick Answer
The IRS can typically audit returns from the past 3 years, but this extends to 6 years if you underreported income by more than 25%. For unfiled returns or fraud, there's no time limit. Currently, the IRS can audit returns from 2023, 2024, 2025, and potentially back to 2020 for substantial underreporting cases.
Best Answer
Diana Flores, Tax Credits & Amendments Specialist
Taxpayers concerned about their audit exposure for past returns
How many years back can the IRS audit?
As of 2026, the IRS can generally audit your 2023, 2024, and 2025 tax returns under the standard 3-year statute of limitations. However, the audit window can extend much further back depending on your specific situation.
The standard 3-year audit window
For most taxpayers who filed accurate returns, the IRS audit period works like this:
This means if you filed all your returns on time with accurate income reporting, your 2022 return and earlier years are now protected from IRS audit under normal circumstances.
When the IRS can audit 6 years back
The audit window extends to 6 years if you substantially underreported your gross income (by more than 25%). This could currently expose these additional years:
Here's a real example of how the 25% test works:
Let's say on your 2021 return, you reported gross income of $60,000, but you actually earned $85,000. You underreported by $25,000.
Common situations that trigger the 6-year window
Missing 1099s from gig work: If you drove for Uber and earned $15,000 but only reported $10,000 in freelance income on a return with $40,000 total income, that's a 12.5% underreporting — still within the 3-year window. But if you missed multiple 1099s totaling $12,000+ in underreporting, you'd hit the 25% threshold.
Cryptocurrency gains: Many taxpayers discovered they owed taxes on crypto transactions from 2020-2021. If you sold $50,000 in Bitcoin for a $20,000 gain but didn't report it on a return showing $60,000 income, that's 33% underreporting — triggering the 6-year statute.
Rental property income: Forgetting to report rental income of $18,000 on a return with $50,000 other income equals 36% underreporting, extending the audit window.
Years with no statute of limitations
The IRS can audit any year if you:
This means if you didn't file your 2019 return, the IRS can still audit and assess taxes for 2019 even today. There's no protection until you file that missing return.
Special circumstances that affect audit periods
Foreign income and FBAR: If you failed to report foreign financial accounts or income, different rules apply. The statute for FBAR violations is 6 years, and foreign income substantial underreporting follows the same 25% rule but often involves larger dollar amounts.
Employment tax issues: If you were supposed to file employment tax returns (Forms 940, 941) as a business owner and didn't, there's no statute of limitations until you file.
Partnership and S-Corp returns: The statute runs separately for entity-level items versus your individual return items flowing through from partnerships and S-corporations.
What you should do to assess your audit risk
1. Review returns from 2020-2025 for any substantial income underreporting
2. Gather all 1099s and W-2s from those years to verify what you reported
3. Calculate if any underreporting exceeds 25% of your reported gross income
4. Consider whether any years remain unfiled
If you discover significant underreporting from 2020-2021, those years may still be within the 6-year audit window. Consider consulting a tax professional about whether to file amended returns proactively.
Current audit reality: IRS capacity constraints
While the IRS legally can audit these years, practical reality matters. The IRS audit rate for individual returns is currently less than 0.4% for most income levels. They're focusing their limited resources on:
For middle-income W-2 employees with simple returns, audit risk remains very low even within the statute of limitations period.
Key takeaway: The IRS can typically audit your last 3 years of returns (2023-2025 currently), extending to 6 years (back to 2020) if you substantially underreported income by more than 25%.
*Sources: [IRC Section 6501](https://www.law.cornell.edu/uscode/text/26/6501), [IRS Publication 556](https://www.irs.gov/pub/irs-pdf/p556.pdf)*
Key Takeaway: Currently, the IRS can audit 2023-2025 returns under normal circumstances, extending back to 2020-2021 for substantial income underreporting over 25%.
Current audit exposure by tax year (as of 2026)
| Tax Year | Filed When | Standard Statute Expires | Extended Statute (25% underreporting) | Current Status |
|---|---|---|---|---|
| 2025 | 2026 | April 15, 2029 | April 15, 2032 | Open for audit |
| 2024 | 2025 | April 15, 2028 | April 15, 2031 | Open for audit |
| 2023 | 2024 | April 15, 2027 | April 15, 2030 | Open for audit |
| 2022 | 2023 | April 15, 2026 | April 15, 2029 | Closed (unless 25% underreporting) |
| 2021 | 2022 | April 15, 2025 | April 15, 2028 | Closed (unless 25% underreporting) |
| 2020 | 2021 | April 15, 2024 | April 15, 2027 | Closed (unless 25% underreporting) |
More Perspectives
Michelle Woodard, Tax Policy Analyst
Taxpayers who have received audit notices or correspondence about older returns
When the IRS contacts you about older returns
If you've received an IRS notice about a return from several years ago, don't panic — but do understand why they can still examine it and what your rights are.
Why the IRS might audit an "old" return
Information matching delays: The IRS sometimes receives 1099s or other information returns late. If they get a 2022 Form 1099-NEC in 2025 showing income you didn't report, they can still audit your 2022 return if it's within the statute.
Related examinations: If the IRS audits your 2024 return and finds issues, they may examine 2022-2023 returns for similar problems. Each year has its own statute, but patterns across years can trigger broader scrutiny.
Amended return complications: If you filed an amended return (Form 1040-X) for 2021, this can extend or restart the statute of limitations for specific items you changed.
What to do if audited on an older return
First, verify the statute: The IRS should only be examining returns within the valid statute of limitations. If they're looking at a return outside the 3-year window, they need to prove substantial underreporting (25%+) for the 6-year statute to apply.
Gather documentation: Older audits are often harder because you may have discarded records. The IRS knows this and sometimes counts on taxpayers being unable to substantiate deductions from 4-5 years ago.
Consider statute of limitations as a defense: If the IRS is examining a return outside the valid statute period, this is a complete defense. They cannot assess additional tax once the statute has expired, even if you actually owe it.
Don't extend unnecessarily: The IRS may ask you to sign Form 872 to extend the statute while they complete their examination. Think carefully — once the original statute expires, you're protected even if their audit finds problems.
Key takeaway: If audited on an older return, verify they're within the proper statute of limitations and consider whether extending the statute is in your best interest.
Key Takeaway: When audited on older returns, verify the IRS is within the proper statute of limitations and be cautious about extending the statute unnecessarily.
Sources
- IRC Section 6501 — Limitations on assessment and collection
- IRS Publication 556 — Examination of Returns, Appeal Rights, and Claims for Refund
Related Questions
Reviewed by Diana Flores, Tax Credits & Amendments Specialist on February 28, 2026
This content is for educational purposes only and is not a substitute for professional tax advice. Consult a qualified tax professional for advice specific to your situation.