Taxterity research

Notice of deficiency: computing the Tax Court petition period

Reviewed 2026-09-15 · AI-assisted draft and editing; sources and limitations remain visible for independent review.

Answer: The period runs from the mailing of the notice of deficiency, not from the day the taxpayer opens it. Section 6213(a) allows a petition within 90 days after the notice is mailed, or 150 days if the notice is addressed to a person outside the United States, and directs that a Saturday, Sunday, or legal holiday in the District of Columbia is not counted as the last day of the period. The same subsection requires the Secretary to specify the last date for filing on the notice itself and provides that a petition filed on or before that specified date is treated as timely. The Tax Court's guidance for petitioners states that the Court cannot extend the time for filing a petition. The timely-mailing rule in section 7502 is available for this filing, because the exception in section 7502(d)(1) reaches the filing of a document in a court other than the Tax Court. Whether the period is jurisdictional, and whether any equitable doctrine can reach it, has been litigated; none of the sources relied on here decides that question. The facts that move the computation are the date of mailing, the address used, and whether the addressee is outside the United States.

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Scope

Jurisdiction: United States — federal

Tax periods: Not period-specific, Code checked 2026-09-15

Assumptions

Exclusions

1. Fix the mailing date before counting anything

Section 6213(a) measures the period from the date the notice authorized by section 6212 is mailed. Receipt date, postmark on the envelope the client kept, and the date of the examination report are all different facts, and only the mailing date starts the statutory count. Record where the mailing date came from and keep the envelope if one survives.

Section 6212(a) authorizes the Secretary to send the notice by registered mail or by the equivalent tracked postal service the subsection names alongside it. Section 6212(b)(1) provides that mailing to the taxpayer at the last known address is sufficient for income tax, gift tax and the chapter 41 through 44 excise taxes, and says the mailing is sufficient even if the taxpayer has died, is under a legal disability, or, for a corporation, has terminated its existence; the parallel estate tax rule is in paragraph (b)(3). That is a rule about the validity of the mailing, and it is the reason a notice can be effective although the taxpayer never saw it.

Where spouses filed a joint return, section 6212(b)(2) permits a single joint notice, but requires a duplicate original to be sent separately to each spouse if either has notified the Secretary that separate residences have been established. Whether that notification was given is a fact to establish, not an assumption.

2. Count the statutory period

The base period is 90 days after mailing. It becomes 150 days if the notice is addressed to a person outside the United States. The trigger in the statute is how the notice is addressed, which is a question about the notice, not a general question about where the taxpayer was living.

Section 6213(a) adds a counting instruction: a Saturday, Sunday, or legal holiday in the District of Columbia is not counted as the last day of the applicable period. The consequence is that the last day moves forward to the next day that is none of those three. A legal holiday in the District of Columbia is not the same list as a holiday in the practitioner's own state, and that difference occasionally decides a date.

Do the count twice and from the statute, not from memory of a prior file. Write down the mailing date, the applicable period, the raw expiry date, and the adjusted date after applying the Saturday, Sunday, and District of Columbia holiday instruction.

3. Reconcile the count against the date printed on the notice

Section 6213(a) requires the Secretary to specify on the notice the last day on which the taxpayer may file a petition, and provides that a petition filed with the Tax Court on or before the last date specified by the Secretary in the notice is treated as timely filed. That sentence gives the printed date independent legal work: it is not merely the Service's arithmetic shown as a courtesy.

So the worksheet has two outputs, not one. If the independent count and the printed date agree, the file is clean. If they diverge, record both, record which is later, and treat the divergence as a question that needs authority applied to the particular notice rather than a typographical error to be ignored.

Do not discard the notice page that carries the specified date. It is the evidence of what the Secretary specified, and it is the document the statutory sentence operates on.

4. Decide and document how the petition reaches the Court

The Tax Court's guidance for petitioners states that the petition is the document that begins a case, that in a deficiency case it must be filed by the 90th day, or the 150th day if the notice is addressed to a person outside the United States, from the date of mailing of the notice, and that in most cases an electronically filed petition must be received no later than 11:59 pm Eastern Time on the last date to file. Under the heading asking whether an extension of time to file a petition is available, the Court's answer is that by law it cannot extend that time.

For a mailed petition, section 7502(a) treats the postmark date as the delivery date if the postmark falls within the prescribed period and the document was deposited, properly addressed with postage prepaid, in the United States mail. Section 7502(d)(1) withholds the section from the filing of a document in any court other than the Tax Court, which means the rule is available for a Tax Court filing rather than withheld from it. This is an easy provision to read backwards, so read the exception text itself before relying on either reading.

Section 7502(c) adds an evidentiary rule for registered mail: registration is prima facie evidence of delivery and the registration date is treated as the postmark date, with authority for the Secretary to extend that treatment by regulation to other tracked mail and to electronic filing. Section 7502(f) allows the Secretary to designate private delivery services that qualify. Whether a particular carrier or service level is currently designated is a fact to verify against current guidance, not an assumption, because the designation list changes.

5. What would change the answer

A different mailing date changes everything downstream; this is the fact most worth documenting first. A notice addressed to a person outside the United States shifts 90 to 150. A last day falling on a Saturday, Sunday, or a District of Columbia legal holiday moves the date forward. A specified last date on the notice that is later than the independent count engages the statutory sentence that treats filing by that date as timely.

A notice mailed to an address that was not the last known address, or a joint-return situation in which separate notices were required, raises a question about the validity of the mailing rather than about arithmetic, and that question is not resolved by a date worksheet. Section 6213(a) also restrains assessment and collection until the period has expired and, if a petition is filed, until the decision of the Tax Court has become final; section 6212(c) restricts further deficiency determinations for the same period once a petition is timely filed. Those consequences are the reason the date matters.

A hypothetical to show the shape of the work, not a precedent: a notice is mailed on a Tuesday and is not addressed outside the United States, so the count is 90 days; the 90th day falls on a Sunday, so the last day moves forward; the notice separately prints a specified last date two days later than that. The worksheet records all three dates and flags the divergence. It does not announce which one controls, because that is a legal conclusion about a specific notice.

Where this page stops, and where to take it next

This page computes and documents a period. It does not decide whether the period is jurisdictional, whether any doctrine can excuse a late filing, or whether a given notice was validly mailed. Those have been litigated and none of the sources used here resolves them, so they need current case law applied to the specific facts by someone who can give advice.

The sibling page in this cluster, Refund claims under section 6511: two clocks and a look-back, handles the opposite posture: a clock that runs from filing and payment rather than from the mailing of a notice, and a ceiling on the amount rather than a bar on the forum. With the notice in hand, ask Taxterity a research question that states the mailing date, the address used and the last date printed on the notice, or have it draft a Federal Tax Memo on the petition period, and then verify each date and citation against the notice and the current statute before anything is filed.

Related research

Official sources

  1. 26 U.S.C. 6213 — Restrictions applicable to deficiencies; petition to Tax Court — Subsection (a): 90-day and 150-day periods; the Saturday, Sunday, and District of Columbia legal holiday counting sentence; the last-date-specified sentence. Preliminary edition read 2026-09-15; no 2025 amendment to subsection (a)
  2. 26 U.S.C. 6212 — Notice of deficiency — Subsection (a) mailing authority; (b)(1) last known address sufficiency; (b)(2) joint returns and duplicate originals; (c) restriction on further deficiency determinations
  3. 26 U.S.C. 7502 — Timely mailing treated as timely filing and paying — Subsection (a)(1) and (a)(2) postmark rule and conditions; (c) registered mail evidentiary rule; (d)(1) exception for a court other than the Tax Court; (f) designated delivery services
  4. United States Tax Court — Guidance for Petitioners: Starting A Case — Deficiency filing deadline of the 90th or 150th day from mailing; 11:59 pm Eastern Time receipt rule for electronic filing; the answer under the extension-of-time heading
  5. IRS Publication 556 — Examination of Returns, Appeal Rights, and Claims for Refund — 90-day letter discussion: 90 days, or 150 days if addressed outside the United States, to petition the Tax Court, and the consequence of not petitioning. Publication revised September 2013

Limitations