Notice of deficiency clock: your last day to petition the Tax Court

How the 90 Days Work

IRC §6213(a) gives you 90 days after the IRS mails the notice to file a petition, or 150 days if the IRS addressed the notice to a person outside the United States. The count runs from the mailing date printed on the notice, not the day the letter reached you. The clock treats the day after the mailing date as day 1.

Section 6213(a) counts the days "not counting Saturday, Sunday, or a legal holiday in the District of Columbia as the last day." So a last day that lands on a weekend or a D.C. holiday moves to the next day that is none of those, and IRC §7503 sets the same rule for tax deadlines in general. The D.C. list includes District of Columbia Emancipation Day, April 16 (D.C. Code §28-2701), which the federal holiday list leaves out.

The IRS also prints a last day to petition on the notice. The last sentence of §6213(a), quoted under the clock, protects a petition you file by that printed date even when it falls after the statutory day. A printed date earlier than the statutory day does not cut your time short, so the clock takes the later of the two as the governing last day. When the two dates differ, filing by the earlier one leaves nothing to dispute.

Writing to the IRS or calling it does not stop the clock. The IRS page says it will work with you during the 90 days, "but this won't extend the time you have to file a petition in Tax Court." The Tax Court page "Guidance for Petitioners: Starting A Case" adds: "By law, the Tax Court cannot extend the time for filing a petition."

Three rules can give you more time, and the clock leaves them out. A bankruptcy case suspends the period while the case bars a petition and for 60 days after (IRC §6213(f)). Service in a combat zone and a federally declared disaster can each postpone the deadline (IRC §7508, §7508A). Each of these only adds time, so when one applies, the clock shows a day earlier than the law allows, never later.

How to File the Petition on Time

You file the petition with the U.S. Tax Court, not with the IRS. The Tax Court takes petitions online through DAWSON, its electronic filing system, and its guidance says the Court must receive an e-filed petition "no later than 11:59 pm Eastern Time on the last date to file" in most cases.

You can also mail a paper petition to United States Tax Court, 400 Second Street, N.W., Washington, D.C. 20217-0002. Under IRC §7502(a), a U.S. Postal Service postmark dated on or before the last day, on a petition properly addressed to the Tax Court with postage prepaid, makes a mailed petition timely even when it arrives later. The Tax Court warns that a private postage meter or an online postage label does not prove the mailing date, and it points to certified or registered mail with a postmarked receipt as stronger proof.

The Tax Court guidance states the cost in one line: "The filing fee is $60." The Court can waive the fee for a petitioner who shows an inability to pay.

The petition asks you to choose a regular case or a small tax case. IRC §7463(a) allows the small tax case procedure when the deficiency in dispute for income tax does not exceed $50,000 for any one taxable year, and the Tax Court has to agree to it. No other court reviews a small tax case decision, and the decision sets no precedent for other cases (IRC §7463(b)). If you check neither box, the Court files the case as a regular case.

You can file the petition yourself. A practitioner files a petition for a client only if the Tax Court has admitted that practitioner to practice before it; the Court's guidance describes help from "an attorney or other person admitted to practice before the Tax Court." Authority to represent someone before the IRS does not carry over to the Tax Court.

What Happens After the Last Day

A deficiency is the extra tax the IRS says you owe. Assessment is the IRS recording that tax as owed on your account, which lets it send a bill and collect. Until the period ends, IRC §6213(a) bars the IRS from assessing the deficiency or levying to collect it, apart from rare jeopardy and termination cases (IRC §6851, §6852, §6861). A timely petition keeps that bar in place until the Tax Court decision becomes final. If the last day passes with no petition, the IRS page says the IRS will assess the proposed changes and send you a bill.

After assessment, the court route runs through payment: you pay the tax, file a refund claim (IRC §7422(a)), and then can sue in a federal district court or the Court of Federal Claims (28 U.S.C. §1346(a)(1)). The appeal channel router covers audit reconsideration, an IRS route for information it never considered. The collection period starts at assessment, and the CSED calculator computes its end.

The notice usually comes with a waiver form, such as Form 5564 with a CP3219A. The Form 5564 decision page sets out what signing it does and what each other path gives up.

Common Questions