You just got a letter that says the IRS plans to assess more tax, plus penalties, and gives you a deadline to challenge it. A Tax Court petition is the formal written request you file with the United States Tax Court asking a judge to review the IRS decision before you have to pay the disputed amount. It is most often used after a Notice of Deficiency, but it can also apply in some collection and innocent spouse cases. Filing the petition starts a court case and tells the court what the IRS got wrong.

This matters because the deadline is strict. In a deficiency case, the petition usually must be filed within 90 days after the IRS mails the notice, under Internal Revenue Code § 6213. Miss that window, and the Tax Court will usually dismiss the case, which can leave you fighting the tax bill another way, often after payment. A petition is not just a complaint letter; it must identify the notice, the tax years involved, and the errors you believe the IRS made.

For someone dealing with a tax problem, a Tax Court petition can stop the dispute from rolling downhill fast, like losing control on black ice in Parley's Canyon. It can preserve your right to challenge the IRS, affect penalties and interest, and shape settlement talks. If the tax issue connects to financial stress after an injury, that timing can make a real difference.