The Tax Court petition process begins with a strict 90-day deadline: after the IRS mails you a notice of deficiency, you have 90 days to file a petition with the U.S. Tax Court, and missing that window by a single day strips the court of jurisdiction over your case.1Office of the Law Revision Counsel. 26 USC 6213 – Restrictions Applicable to Deficiencies; Petition to Tax Court Filing gets you into the only federal court where you can challenge the bill without paying it first. What follows the petition is a structured sequence of settlement talks, pretrial exchanges, and a bench trial in front of a single judge.
The 90-Day Filing Window
The clock starts on the date the IRS mails the notice, not the date you open it. If the notice is addressed to someone outside the United States, the window is 150 days. Saturdays, Sundays, and District of Columbia legal holidays don’t count if they fall on the last day.1Office of the Law Revision Counsel. 26 USC 6213 – Restrictions Applicable to Deficiencies; Petition to Tax Court
There is no extension and no exception. If you miss the deadline, your remaining options are to pay the full assessed tax and then sue for a refund in a U.S. district court or the Court of Federal Claims. Pay first, litigate second.
What the Petition Must Include
A Tax Court case begins when you file a petition in response to the IRS notice.2United States Tax Court. Guidance for Petitioners – Starting a Case The petition has to state your full name, your state of legal residence (or principal place of business for an entity), your mailing address, and the IRS office where your return was filed. It also has to identify the specific tax years in dispute, the amounts of deficiency and any penalties, and a clear statement of the errors you believe the IRS made.3United States Tax Court. Rule 34 – Petition
Attach a copy of the IRS notice you are challenging. The court publishes official forms, and using them cuts the risk of a filing being rejected for a formatting problem.
One detail catches almost everyone off guard: your Social Security number does not go in the petition. It goes on a separate document, Form 4 (Statement of Taxpayer Identification Number), which stays out of the public court file. Everything else you file becomes part of the public record, so redact sensitive numbers before submitting.4United States Tax Court. Petition Kit Rule 27 spells out the redaction requirements: no SSNs or EINs at all, only the year of a date of birth, initials for minor children, and only the last four digits of financial account numbers.5United States Tax Court. Rule 27 – Privacy Protection for Filings Made with the Court The clerk’s office doesn’t review your filings for compliance; the responsibility is yours.
How to File
The Tax Court’s electronic filing system, DAWSON, is the standard route. You create an account, upload the petition and the IRS notice together, and pay the $60 filing fee online.6United States Tax Court. Court Fees If you cannot afford the fee, you can apply for a waiver. Once the court processes the submission, you get a docket number that follows the case through to a decision.7United States Tax Court. DAWSON
You can also mail the petition to the court’s headquarters in Washington, D.C. The “timely mailed, timely filed” rule treats the postmark date as the filing date, so a petition postmarked on day 90 counts even if the envelope reaches the court later.8Office of the Law Revision Counsel. 26 U.S. Code 7502 – Timely Mailing Treated as Timely Filing and Paying Use certified or registered mail so you have proof. Private delivery services do not always qualify, and if you can’t prove the mailing date, the court may dismiss the case.
Small Tax Case or Regular Case
If the amount in dispute is $50,000 or less for any single tax year, you can elect the small tax case procedure, often called an “S case.” The trial is less formal, evidentiary rules are relaxed, and the court itself sets those rules rather than applying the Federal Rules of Evidence.9Office of the Law Revision Counsel. 26 USC 7463 – Disputes Involving $50,000 or Less
There is a cost to that simplicity. A small case decision cannot be appealed by either side, and it doesn’t set precedent. If you win, the finality helps. If you lose, there is no second chance. Both you and the court have to agree to the election, and either party can ask that the case be moved back to the regular track.
Who Can Represent You
You can represent yourself, and many petitioners do. If you want a representative, licensed attorneys in good standing with a state bar, the D.C. bar, or the U.S. Supreme Court bar can be admitted to practice before the Tax Court after applying under Rule 200.10United States Tax Court. Rule 200 – Admission to Practice and Periodic Registration Fee Non-attorneys can also be admitted, but only after passing a written examination the court administers at least every two years and completing a character and fitness review.11United States Tax Court. Guidance for Practitioners
If your income does not exceed 250 percent of the federal poverty level, you may qualify for free or low-cost representation from a Low-Income Taxpayer Clinic. These clinics are federally funded, represent eligible taxpayers in IRS disputes including Tax Court cases, and also serve people for whom English is a second language.12GovInfo. 26 USC 7526 – Low-Income Taxpayer Clinics The IRS website publishes a directory. Contact one early; waiting can push you past the filing deadline.
Settlement With IRS Appeals
Most Tax Court cases never reach trial. After you file the petition and the IRS files its answer, the case can be referred to the IRS Independent Office of Appeals for settlement negotiations. Appeals officers can compromise on both factual and legal issues in a docketed case, and the process is less adversarial than a courtroom.13Internal Revenue Service. Procedures for Processing and Settling Docketed Cases
Deadlines constrain the process. For small cases and regular cases involving $50,000 or less per year, IRS Counsel can recall the case from Appeals after six months, and if Counsel doesn’t recall it, Appeals must return the case at least 30 days before the calendar call. For larger cases, Appeals returns the file when settlement isn’t possible or within 10 days after the case appears on a trial calendar.14Internal Revenue Service. Campus Appeals Docketed Cases A settlement is formalized in a stipulated decision that both parties sign and the court enters.
Pretrial Steps if the Case Doesn’t Settle
Tax Court pretrial practice is more structured than in most federal courts, and it rewards preparation.
Informal Information Exchange
Before either party can use formal discovery, the Tax Court requires a good-faith attempt to get the information informally. In practice, the IRS attorney sends a written request (sometimes called a Branerton letter) proposing a conference and asking for documents. The request has to be specific and give you enough time to organize records and respond.15Internal Revenue Service. Gathering Information from the Petitioner
Stipulations
Rule 91 requires both sides to agree on as many undisputed facts and documents as possible before trial. This is not optional. The stipulation becomes part of the record, so the judge starts with an agreed factual foundation before hearing contested testimony.16United States Tax Court. Rule 91 – Stipulations for Trial Judges notice when parties refuse to stipulate to obvious facts, and it rarely helps.
Formal Discovery
When informal efforts fall short, Rule 70 allows formal discovery on any relevant, non-privileged matter, including written interrogatories, document requests, and depositions.17United States Tax Court. Rule 70 – General Provisions Discovery fights are less common in Tax Court than in ordinary federal litigation because the stipulation process and informal exchange resolve most gaps first.
Expert Witnesses
An expert witness report has to be served on the opposing party and submitted to the court no later than 30 days before the trial calendar is called. The report includes the expert’s complete opinions and their basis, data considered, exhibits, qualifications and publications from the past 10 years, cases where the expert testified in the previous four years, and compensation. Miss the deadline and the testimony is excluded, unless you can show good cause and no prejudice to the other side.18United States Tax Court. Rule 143 – Evidence
Pretrial Memorandum
Each party files a pretrial memorandum with the judge and the opposing party at least 14 days before the trial session begins. The memorandum identifies the legal issues, lists each expected witness with a summary of anticipated testimony, gives a chronological narrative of the facts, and lays out the legal argument with supporting authorities.19United States Tax Court. Standing Pretrial Order The judge reads it before hearing any testimony, so this is often where cases are effectively won or lost.
Trial and Burden of Proof
Tax Court trials are bench trials. One judge hears the evidence and decides the case. Regular cases follow the Federal Rules of Evidence; small cases use the court’s own relaxed rules.20Office of the Law Revision Counsel. 26 USC 7453 – Rules of Practice, Procedure, and Evidence Each side opens with a summary, witnesses give sworn testimony and are cross-examined, and expert reports that were properly submitted come in as the expert’s direct testimony.18United States Tax Court. Rule 143 – Evidence
The judge almost never rules from the bench. Both parties file post-trial briefs tying the evidence to the legal issues, and the judge later issues a written opinion with detailed findings of fact and legal conclusions. Months can pass between trial and decision, and complex cases can take well over a year.
In most cases the taxpayer carries the burden of proving the IRS determination is wrong. The burden can shift to the government if you introduce credible evidence on a factual issue, have met all substantiation and recordkeeping requirements, and cooperated with reasonable IRS information requests.21Office of the Law Revision Counsel. 26 U.S. Code 7491 – Burden of Proof Corporations, partnerships, and trusts face additional requirements before the shift applies.
Two areas where the IRS always carries the burden: penalties and fraud. The IRS must produce evidence to justify any penalty, addition to tax, or additional amount asserted against an individual, and civil fraud has to be proved by clear and convincing evidence, a higher standard than the usual preponderance.21Office of the Law Revision Counsel. 26 U.S. Code 7491 – Burden of Proof
Appealing the Decision
If you lose a regular case, you can appeal to the U.S. Court of Appeals, generally the circuit where you lived when you filed the petition. The appellate court reviews Tax Court decisions the same way it reviews bench trials from district court.22Office of the Law Revision Counsel. 26 USC 7482 – Courts of Review File the notice of appeal with the Tax Court clerk within 90 days after the decision is entered. If one party files a timely notice, the other gets 120 days from the decision date to file its own. A pending motion to vacate or revise pauses the appeal clock.23Legal Information Institute (Cornell Law School). Federal Rules of Appellate Procedure Rule 13 – Appeals from the Tax Court
Filing an appeal does not stop IRS collection. To pause collection, you have to post a bond with the Tax Court. The court sets the amount, capped at double the disputed deficiency, backed by an approved surety, and conditioned on payment of whatever is ultimately determined, including interest.24Office of the Law Revision Counsel. 26 USC 7485 – Bond to Stay Assessment and Collection Partial payments during the appeal can support a request to reduce the bond proportionally.
Small tax case decisions are final. Neither side can appeal, and the decision carries no precedential weight in later cases.9Office of the Law Revision Counsel. 26 USC 7463 – Disputes Involving $50,000 or Less