How Far Back Can the IRS Audit You? Statute of Limitations Explained (2026)

For most taxpayers, the IRS has three years from the later of the return due date or the date the return was actually filed to initiate an examination. This three-year period is the standard statute of limitations for assessment under the Internal Revenue Code. For example, if you filed your 2022 tax return on April 15, 2023, the IRS would generally have until April 15, 2026 to audit that return under the standard rule. If you filed before the due date, the clock typically starts from the original due date, not the early filing date. See also: how to get your W-2 online.

The IRS audit lookback period extends to six years if you omitted from your gross income an amount that exceeds 25% of the gross income reported on your return. This rule is designed to give the IRS additional time to detect significant underreporting. Substantial omissions can arise from unreported self-employment income, business receipts, investment gains, or income from foreign accounts. The six-year period begins from the date the return was filed (or the due date, if later). If you believe you may have substantially underreported income in a prior year, consult a tax attorney or CPA before the statute of limitations for that period closes. See also: the 846 refund issued code.

The IRS has no statute of limitations in two situations: when you filed a fraudulent return, or when you never filed a return at all. If the IRS determines that a return was fraudulent — for example, that you intentionally misrepresented income or claimed false deductions — it may assess taxes for that year at any time, regardless of how long ago the return was filed. Similarly, if you failed to file a required return, the statute of limitations never begins running, meaning the IRS retains the right to assess taxes for that year indefinitely. These situations may also involve civil fraud penalties (75% of underpayment) or criminal prosecution. See also: how do tax write-offs work.

Several additional situations may affect how far back the IRS can audit you: See also: effective tax rate calculator.

• Foreign financial accounts (FBAR and FATCA): Failure to report foreign bank accounts or assets may trigger extended or unlimited lookback periods under FBAR rules enforced by the Financial Crimes Enforcement Network (FinCEN) and under FATCA provisions.
• Amended returns: Filing an amended return (Form 1040-X) does not typically restart the statute of limitations for the original return, though it may for changes made on the amendment itself.
• Carryforward items: If your return involves items that carry forward to future years — such as net operating losses — the IRS may examine earlier years to verify the originating amounts in connection with later-year audits.

The IRS recommends keeping tax records for a minimum of three years from the date you file your return, which covers the standard audit window for most taxpayers. However, given the six-year window for substantial underreporting, many tax professionals recommend keeping supporting records for six years as a precaution. Records related to property — including the purchase price, improvements, and depreciation — should generally be kept until you sell the property plus three to six years afterward, since these affect the calculation of gain or loss on the sale. If you have never filed or if fraud is a concern, records should be kept indefinitely. See also: how to pay no taxes on rental income.

The IRS selects returns for examination through several methods, including computer screening that compares return line items to statistical norms, random selection, and related-examination reviews where a person's return is connected to another return being audited. Common factors that may increase audit attention include significant discrepancies between reported income and information on file with the IRS (such as W-2s and 1099s), unusually large deductions relative to income, and business losses claimed over multiple consecutive years. Receiving an audit notice does not mean you have done something wrong — many audits are correspondence audits (by mail) requesting documentation for specific items. This content is for informational purposes only; consult a CPA, enrolled agent, or tax attorney for guidance specific to your situation. See also: how tax identity theft can occur.