You have the right to know the IRS’s timeline for, or finality of, certain interactions with you. You have the right to know: the maximum amount of time you have to challenge the IRS position if you’re under audit; the maximum amount of time the IRS has to audit a tax year or collect a tax debt; and when the IRS has completed an audit. The IRS generally has 3 years from the date taxpayers file their returns to assess any additional tax for that tax year, with some exceptions. These instances include when taxpayers fail to file returns for specific years or file false or fraudulent returns. In such cases, the IRS has an unlimited amount of time to assess tax for those tax years.