Equitable tolling is the legal doctrine that lets a court excuse a missed deadline when the person missed it for a good reason despite diligent effort. It exists throughout American law. In tax law, whether it applies depends on which deadline you missed, and the Supreme Court has drawn the line in two important cases.

This guide explains those two decisions, what they held and what they mean if you are on the wrong side of a tax deadline.

Brockamp: no equitable tolling for refund claims

In United States v. Brockamp, 519 U.S. 347 (1997), the taxpayers had overpaid, filed refund claims years after the section 6511 deadline and argued that disabilities, including senility, explained the delay. The Ninth Circuit allowed equitable tolling. The Supreme Court reversed.

The Court held that courts cannot toll, for nonstatutory equitable reasons, the time and related amount limitations for filing tax refund claims in section 6511. It explained that section 6511 sets out its limitations in unusually emphatic form, in highly detailed technical language, repeats them several times in different ways, imposes substantive limits on the amount of recovery and lists explicit exceptions that do not include equitable tolling. It also pointed to the scale of tax administration and the administrative problems that case-by-case equitable exceptions would create.

Congress responded with a narrow statutory fix for financial disability, now in section 6511(h). It did not create a general equitable exception. The guide on financial disability tolling covers that rule.

Boechler: the CDP petition deadline can be tolled

Twenty-five years later, in Boechler, P.C. v. Commissioner, 596 U.S. 199 (2022), the Court reached a different result for a different deadline. A law firm requested a collection due process hearing, lost and filed its Tax Court petition one day after the 30-day deadline in section 6330(d)(1). The Tax Court dismissed for lack of jurisdiction, and the Eighth Circuit affirmed.

A unanimous Supreme Court reversed. It held that the 30-day time limit to file a petition for review of a collection due process determination is a nonjurisdictional deadline subject to equitable tolling. The Court explained that a procedural requirement is jurisdictional only if Congress clearly states that it is, and the text of section 6330(d)(1) does not clearly tie the deadline to the Tax Court's jurisdiction. Nonjurisdictional deadlines are presumptively subject to equitable tolling, and nothing rebutted that presumption.

The Court distinguished Brockamp directly. It said section 6330(d)(1)'s deadline is not written in emphatic form or with detailed, technical language, is not reiterated multiple times and admits only a single exception, compared with the multiple exceptions in section 6511. The Court left it to the lower courts to decide on remand whether Boechler was actually entitled to tolling on its facts.

What the two cases mean together

The decisions are not in conflict. They apply the same framework to different statutes. The questions are whether the deadline is jurisdictional, and if not, whether anything rebuts the presumption that it can be equitably tolled.

For the refund claim deadline in section 6511, Brockamp answers no tolling, and the statutory exceptions are the only exceptions. For the CDP petition deadline in section 6330(d)(1), Boechler answers that tolling is available in appropriate cases.

For other tax deadlines, the answer depends on the statute's text and structure. Boechler itself noted that the Commissioner relied on lower-court cases holding that the deficiency petition deadline in section 6213(a) is jurisdictional, and said those cases mostly predated the Court's recent efforts to discipline the use of the jurisdictional label. The Court did not decide the section 6213(a) question. Since 2022, the question of the 90-day deficiency petition deadline has been litigated in the Tax Court and in federal courts of appeals.

Practical lessons

  • Treat every deadline as absolute when planning. Equitable tolling is an argument for after something has gone wrong, not a strategy.
  • For refund claims, there is no equitable safety net. Only the statutory exceptions, such as financial disability, consents, special periods and mitigation, can extend the time. See the guides to the refund claim deadline and the mitigation provisions.
  • For a missed CDP petition deadline, Boechler opens the door to an equitable tolling argument. Whether it succeeds depends on the facts, including the reason for the delay and the diligence shown.
  • For the 90-day deficiency petition deadline, do not assume tolling is available. The law has been contested since Boechler, and the answer may depend on the court. Use the date printed on the notice, which IRC 6213(a) treats as controlling if you file by it, and the timely mailing rule.
  • Document everything. If you ever need to argue for tolling, your evidence of diligence and of the circumstances that prevented a timely filing will decide the case.

Triage for a missed deadline

If you think you missed a tax deadline, do not jump straight to equitable tolling. Work through the statutory rules first, because they are more reliable.

  • Was it actually missed? Check the postmark under IRC 7502, the weekend and holiday rule under IRC 7503 and, for a deficiency petition, the last date printed on the notice, which IRC 6213(a) treats as controlling.
  • Did the deadline ever start? A notice not mailed to your last known address may not have started the clock.
  • Was the deadline suspended or extended by statute? Consents, disability, bankruptcy and the other statutory rules may have moved the date.
  • Is there another path? A missed CDP hearing request may still leave an equivalent hearing. A missed deficiency petition may still leave a refund claim and suit after payment, or audit reconsideration. The library article on challenging an IRS assessment maps those doors.
  • Only then, ask whether the deadline is one that can be equitably tolled, and whether the facts support it.

Statutory tolling is different

Equitable tolling is judge-made relief. Statutory tolling is relief Congress wrote. The suspension rules for the collection statute in section 6503, the notice of deficiency suspension in section 6503(a), the financial disability rule in section 6511(h) and the consent rules in section 6501(c)(4) are all statutory. They apply when their terms are met, without any showing of diligence or fairness.

Section 6330(e)(1) is a good example of how statutory tolling works. When a collection due process hearing is requested, it suspends the collection statute in section 6502, and it also suspends the periods in sections 6531 and 6532, for as long as the hearing and appeals are pending, with a 90-day floor after the final determination. No one has to prove diligence for that suspension to apply. It happens because the statute says so.

Most of this site is about statutory rules for that reason. They are predictable. The guide on what suspends the collection statute and the guide on notices of deficiency cover the most important ones.

The bottom line

There is a human side to these cases. The taxpayers in Brockamp were elderly or ill, and the result was harsh. The firm in Boechler missed its deadline by a single day. The law in both cases turned on statutory text, not sympathy. That is the most important lesson for anyone facing a tax deadline: the safest assumption is that the calendar will be enforced exactly as written, and the time to protect yourself is before the date, not after.

Under United States v. Brockamp, 519 U.S. 347 (1997), the section 6511 refund deadlines cannot be equitably tolled; only statutory exceptions apply. Under Boechler, P.C. v. Commissioner, 596 U.S. 199 (2022), the 30-day collection due process petition deadline in section 6330(d)(1) is nonjurisdictional and can be equitably tolled in appropriate cases. For other deadlines, the answer depends on the statute. Plan as if no deadline will ever be excused, because most of the time it will not be.