How to File a Petition in U.S. Tax Court: Deadlines, Forms, and Common Mistakes

The Notice of Deficiency and the Filing Deadline

A notice of deficiency, often called a “90-day letter,” is the IRS’s formal determination that additional tax is owed. Under Internal Revenue Code section 6213(a), a taxpayer may file a petition with the Tax Court within 90 days after the notice is mailed, or within 150 days if the notice is addressed to a person outside the United States.

The period runs from the date the notice is mailed, not the date it arrives. If the last day falls on a Saturday, Sunday, or legal holiday in the District of Columbia, the petition is timely if filed on the next business day. The IRS normally lists the last day to file on the notice, and section 6213(a) treats a petition filed by that date as timely.

The Tax Court cannot extend the time to file a petition. A petition filed after the deadline is generally dismissed. At that point the usual path is to pay the tax, file a claim for refund with the IRS, and, if the claim is denied or not acted on within six months, sue for a refund in federal district court or the U.S. Court of Federal Claims.

Other IRS notices carry different deadlines. A petition challenging a collection due process determination is generally due within 30 days of the determination under section 6330(d)(1), and a petition for review of an innocent spouse determination is due within 90 days after the IRS mails its final determination under section 6015(e).

The Forms the Court Provides

The Tax Court’s standard petition is Form 2. A petition can also be prepared through the petition generator in DAWSON, the Court’s electronic filing system, or drafted independently if it meets the Court’s rules.

Under Tax Court Rule 34, a petition in a deficiency case identifies the notice being challenged, the tax years and amounts in dispute, clear and concise assignments of each error the taxpayer believes the IRS made, and the facts supporting each assignment. Rule 34 also provides that any issue not raised in the assignments of error will be deemed conceded, so the list of errors should be complete even if each statement is brief.

A complete copy of the notice of deficiency, including the explanation of adjustments, should be attached, with the Social Security number redacted. Tax returns, receipts, and other evidence should not be attached to the petition. The Court also asks for two companion forms:

Form 4, Statement of Taxpayer Identification Number. This is the only document that should show the taxpayer’s Social Security number or other identification number. It is not part of the public case record.

Form 5, Request for Place of Trial. This tells the Court the city where the taxpayer would like the trial held. A taxpayer may choose a city outside his or her home state, although some cities are available only for small tax cases.

A business that files a petition also submits a Corporate Disclosure Statement (Form 6).

How to File and What It Costs

Electronically. Petitions may be filed through DAWSON. In most cases the Court must receive an electronically filed petition by 11:59 p.m. Eastern time on the last day to file.

By mail. Paper petitions go to the United States Tax Court, 400 Second Street, N.W., Washington, D.C. 20217-0002. The Court generally treats a mailed petition as timely if it arrives in an envelope bearing a legible U.S. Postal Service postmark dated within the filing period. Certified or registered mail, or a private delivery service designated by the IRS, provides stronger evidence of the mailing date. A private postage-meter stamp does not prove timely mailing.

In person. Petitions may be hand-delivered to the Court in Washington, D.C., between 8 a.m. and 4:30 p.m. Eastern time.

The Court does not accept petitions by fax or email, and a petition should be filed only once, not both electronically and on paper. The filing fee is $60, payable through Pay.gov or by check or money order. The Court may waive the fee for a petitioner who establishes an inability to pay.

Common Mistakes

Counting from the wrong date

The 90 days run from the date the notice was mailed. Waiting for a reply from the IRS, or for more time to understand the notice, does not pause the clock.

Writing to the IRS instead of the Court

The petition must be filed with the Tax Court. Correspondence with the IRS, including a request for an IRS Appeals conference, does not extend the deadline. The Court’s guidance notes that a taxpayer who believes the case was already settled, but then receives a notice of deficiency, should still file a petition within the period stated in the notice.

Leaving out issues

Each disputed adjustment, including any penalty, should be listed as a separate assignment of error with supporting facts. Adding issues later may require the Court’s permission to amend the petition.

Missing pieces

Omitting the copy of the notice, Form 4, or the filing fee (or an application to waive it) can delay the case.

Choosing small tax case status without weighing the trade-off

If the amount in dispute qualifies (in a deficiency case, $50,000 or less for any one year, including additions to tax and penalties), a taxpayer may elect small tax case procedures. They are less formal, but the decision cannot be appealed by either side.

What Happens After Filing

An attorney from the IRS Office of Chief Counsel represents the IRS. Under Rule 36, the IRS generally has 60 days from service of the petition to file an answer. After the answer, an IRS employee typically contacts the taxpayer to schedule a conference to discuss settlement and the facts that can be agreed. Docketed cases are often referred to the IRS Independent Office of Appeals for settlement consideration.

If the case does not settle, the Court generally issues a notice setting the case for trial about five months before the trial date, along with a standing pretrial order that explains how each side must prepare. There is no fixed timetable; the length of a case depends on the issues, whether the parties settle, and the trial calendar.