Statute of Limitations for Tax Fraud and Tax Evasion

Written by Sam Brotman, J.D., LL.M. (Taxation), MBA — Managing Attorney, Brotman Law  ·  Updated May 2026

The Short Answer: 6 Years for Felonies, 3 for Misdemeanors

The general federal criminal statute of limitations is 5 years under 18 U.S.C. § 3282. Section 6531 is an explicit exception — Congress extended the limitation period for tax crimes to 6 years because tax investigations take longer to develop and the underlying conduct is harder to detect. That extra year matters. It means a return filed in April 2019 can still be the basis for a federal indictment through April 2025.

This page is about the criminal statute only. The civil side — the IRS's 3-year window to assess additional tax (6 years in cases of substantial omission, unlimited in cases of fraud) — is controlled by § 6501 and is a different legal framework. See the civil audit SOL page for that analysis.

Criminal SOL by Offense Type

The chart below covers the most commonly charged criminal tax statutes and related offenses. When a federal tax investigation expands, DOJ Tax almost always layers multiple statutes — the primary tax charge plus conspiracy, plus potentially wire fraud or false statements. Each charge runs its own SOL clock.

The practical consequence of that table: a single set of returns can carry multiple overlapping SOL windows from different statutes. DOJ Tax is experienced at structuring indictments to maximize which charges can still be brought within applicable limitations periods.

When the Clock Starts Running

For tax evasion under § 7201, the courts have held that evasion is complete at the last affirmative act — typically the filing of the false return, the last false statement signed, or the last act of affirmative concealment (like moving funds offshore or creating a false document). This matters because a taxpayer who filed a false return in April 2018 but continued making false representations to the IRS during a 2021 audit may have extended the clock by that later conduct.

For filing a false return under § 7206(1), the SOL generally runs from the date the return was filed — not the due date if the return was filed late. A return filed in October 2018 on extension for the 2017 tax year has a criminal SOL that runs from October 2018, not April 2018. That is a meaningful distinction.

For failure to file under § 7203, the SOL runs from the due date of the return — the date by which the taxpayer was obligated to file. A 2017 return due April 15, 2018 starts a 3-year misdemeanor clock from April 15, 2018, regardless of when (or whether) the return is eventually filed.

The key distinction between evasion and failure to file goes beyond the limitation period. Evasion requires proof of an affirmative act to evade tax — it is not enough that tax went unpaid. Failure to file is simply the non-act of not filing. Both are crimes, but they are charged based on the nature of the conduct, not just the outcome.

Civil SOL vs. Criminal SOL: Two Separate Clocks

This distinction confuses a lot of people, and it matters. When the IRS opens a civil examination and you sign a Form 872 extending the civil SOL, you are extending the IRS's right to assess additional civil tax. You are not extending or waiving the criminal SOL. Those are controlled by different statutes and different legal frameworks.

Similarly, the unlimited civil assessment period for fraudulent returns under § 6501(c)(1) — which allows the IRS to assess tax indefinitely where fraud is established — has nothing to do with the 6-year criminal limitation period. The civil case might stay open indefinitely; the criminal window is still 6 years from the date the offense was complete.

The flip side is equally true and worth understanding: a civil examination that is running in year 4 or 5 after a return was filed does not mean the criminal clock has stopped. Both clocks are running at the same time. A taxpayer who receives a civil IDR (Information Document Request) in year 4 of an examination may be simultaneously inside the window for criminal prosecution. Coordinating civil and criminal exposure requires treating them as the distinct legal tracks they are.

Tolling and Suspension Events

Several events can pause — or extend — the criminal SOL for tax crimes.

Indictment or Information

Once a grand jury returns an indictment, or DOJ Tax files a criminal information, the statute of limitations is tolled. The practical effect: the government needs to indict within the applicable SOL period, but once the indictment is filed, the clock stops. Delays in bringing the case to trial after indictment are governed by the Speedy Trial Act (18 U.S.C. § 3161), not by the SOL.

Fugitive Status

If a person flees or is outside the United States to avoid prosecution, the period of absence does not count toward the SOL under 18 U.S.C. § 3290. This provision is rarely litigated in ordinary tax cases but is relevant in international tax matters where a taxpayer has left the country during or after an investigation.

Foreign Evidence Requests: 31 U.S.C. § 3292

This is the tolling provision that practitioners in international tax cases need to know. Under 31 U.S.C. § 3292, a federal court can suspend the SOL — for up to 3 years — when the government has submitted a formal request for evidence to a foreign country under a treaty or executive agreement and that request is pending. The suspension runs from the date the request is submitted to the date the government receives the final response, but cannot exceed 3 years.

In practice, this means a case involving unreported foreign accounts or foreign income can have its criminal window extended from 6 years to up to 9 years. DOJ Tax has used § 3292 suspensions in FBAR and offshore account prosecutions to preserve the ability to bring charges while foreign evidence is being gathered through Mutual Legal Assistance Treaties (MLATs).

Conspiracy Charges: How DOJ Tax Extends Its Reach

This is one of DOJ Tax's most effective structural tools. A scheme that began in 2015 with a false return might feel like it's outside any statute of limitations by 2025. But if the conspiracy had an overt act in 2021 — a wire transfer, a document submitted, a meeting — the 5-year clock runs from that 2021 act, not from 2015. The government charges back through the full scope of the scheme even if some individual acts are time-barred as standalone offenses.

Co-conspirator overt acts also count. If a co-defendant or co-conspirator — an accountant, a promoter, a business partner — took an overt act within the 5-year window, that act can anchor the conspiracy charge against all members of the conspiracy, even those who took no personal action within the period. Courts have upheld this application consistently.

DOJ Tax layering looks like this in practice: the core tax evasion charges cover the years within the 6-year SOL; the conspiracy count is charged separately and covers the full duration of the scheme back to its inception, so long as the last overt act falls within 5 years. That structure allows the government to paint a complete picture of the conduct to the jury while staying within limitations.

If you have been approached by investigators or have reason to believe you may be a target or subject of a grand jury investigation, the conspiracy question — who else was involved, and what acts did they take recently — is one of the first things defense counsel should be mapping.

FBAR Criminal SOL: A Third Clock

The Bank Secrecy Act requires U.S. persons with foreign financial accounts exceeding $10,000 to file an FBAR (FinCEN Form 114) annually. Willful failure to file, and filing a false FBAR, are criminal offenses under § 5322. The 5-year SOL for those offenses runs from the date of the violation — the FBAR due date for failure to file, or the date of filing for a false FBAR.

What makes FBAR exposure distinctive is that it layers on top of the criminal tax exposure, not instead of it. A taxpayer with unreported foreign accounts and underreported foreign income can face:

• Criminal tax charges under § 7201 or § 7206(1) for the false returns — 6-year SOL
• Criminal FBAR charges under § 5322 — 5-year SOL
• Conspiracy under § 371 — 5-year SOL from last overt act
• Civil FBAR penalties under § 5321 — up to $10,000 per non-willful violation, $100,000+ or 50% of account value per willful violation, with a 6-year civil SOL

Those clocks run independently. And if the case involves foreign evidence gathering under a treaty, the § 3292 suspension can toll the tax and potentially the FBAR criminal SOL simultaneously.

If you have undisclosed foreign accounts and are weighing disclosure options, the interaction of these limitation periods is a central part of the analysis. The FBAR quiet disclosure page addresses some of those considerations, but the criminal exposure question warrants its own evaluation with counsel.

False Statements to IRS Agents: 18 U.S.C. § 1001

Section 1001 is often called the "lying to investigators" statute. It does not require that the underlying conduct being investigated was itself criminal. The false statement is the crime. And it carries up to 5 years in prison.

The practical consequence for taxpayers under audit: a civil examination can create fresh criminal exposure through the audit process itself, entirely separate from whatever is on the returns being examined. A taxpayer who filed a return in 2018 — whose original filing might be approaching or past the criminal SOL — can create a § 1001 exposure in 2024 by making a false statement to an examiner about that same return. The new false statement has a 5-year SOL running from 2024.

This is one reason defense counsel consistently advises clients to route all IRS contact through counsel once criminal exposure is a realistic concern. It is not about stonewalling the IRS. It is about ensuring that no statement — oral or written — creates additional criminal exposure that wouldn't otherwise exist.

The Cold Case Question: Can They Really Prosecute Old Returns?

Yes. And they do.

A reasonable working assumption is that the government will not pursue criminal charges on returns from 5 or 6 years ago. That assumption is wrong with some regularity. DOJ Tax Division has a relatively small number of attorneys handling a large volume of referrals. Investigations that begin as routine civil examinations or whistleblower referrals can take 3 to 4 years to develop before a criminal referral is made to the Criminal Investigation (CI) division of the IRS. By the time CI has built the case and DOJ Tax has reviewed it, the applicable returns may be approaching — but not yet past — the 6-year window.

A practical illustration: a taxpayer files a false return in April 2020. A civil audit opens in 2022. In 2023, the revenue agent identifies indicators of fraud and makes a referral to CI. CI investigates through 2024 and makes a criminal referral to DOJ Tax in early 2025. DOJ Tax reviews and authorizes prosecution in late 2025. An indictment is returned in March 2026. That is just inside the 6-year window from April 2020. Every step of that timeline is realistic.

Conspiracy charges extend the analysis further. If any overt act in that scheme occurred within 5 years of the indictment — a wire transfer, a document produced in response to an IDR, a conversation with a promoter — the conspiracy count reaches back through the full scheme regardless of when individual tax years fall.

The point is not to create alarm where none is warranted. Most civil audits do not become criminal cases. But the idea that old exposure is categorically resolved exposure is not accurate, and it should not be the basis for strategic decisions about disclosure or cooperation.

What to Do When the SOL Is Approaching

A statute of limitations approaching its end is one of the highest-leverage moments in a criminal tax matter. It creates real options — and real risks.

Voluntary Disclosure

The IRS Criminal Investigation Voluntary Disclosure Program (VDP) offers a pathway for taxpayers with criminal exposure to come forward before an investigation begins, with a general commitment from the IRS not to recommend criminal prosecution. The program has strict requirements — disclosure must be timely (before a criminal investigation has begun), truthful, and complete, and the taxpayer must cooperate in determining the correct tax liability and pay that liability in full.

The SOL is relevant to VDP strategy in two ways. First, if the SOL has already run on a tax year, that year may be outside the scope of a voluntary disclosure, simplifying the analysis. Second, the approaching SOL on open years can create urgency around when to file — the IRS's VDP requires disclosure before CI opens an investigation, and an investigation that opens in month 58 of a 72-month window means the remaining window is narrower.

Proffer Agreements

If you are a subject or target of an investigation and the SOL is approaching, a proffer agreement can be one tool for obtaining information about the government's case while protecting your ability to negotiate. A proffer is a protected communication — statements made under a proffer agreement cannot generally be used against the speaker in the government's case-in-chief, though there are exceptions. The proffer agreement page covers those rules in detail.

When the SOL is close, the timing of a proffer matters. If the government is approaching the window and has not yet obtained an indictment, a proffer that opens a dialogue can either accelerate the government's decision to indict or create conditions for a resolution short of indictment. Defense counsel needs to evaluate that balance carefully.

DOJ Tax Civil Division Referral

Not every investigation ends in criminal charges. The DOJ Tax Division has both a Criminal Enforcement Section and a Civil Trial Section. Cases that do not meet the evidentiary threshold for criminal prosecution may be referred for civil collection or civil fraud penalty assessment instead. Understanding where a case is in DOJ's referral process — and whether criminal prosecution remains actively on the table — requires access to defense counsel who can assess the posture of the investigation from the available signals.

If you are in that position, the question is not just what the statute of limitations says. It is where the government actually is in its investigation, and what options are available given that reality. That analysis is specific to the facts. A 15-minute call is a reasonable first step.