IRS Math Error Letters to Show Calculations and 60-Day Abatement Deadline Under New Law
Taxpayers will now receive math error notices that include the IRS's calculations and a clear 60-day deadline to request an abatement, under the Internal Revenue Service Math and Taxpayer Help Act (H.R. 998), which President Donald Trump signed into law on 1 December 2025. In a 1 December 2025 news release, the US House of Representatives Ways and Means Committee said that the legislation addresses long-standing concerns that taxpayers were not informed of their right to dispute math error adjustments within 60 days, often resulting in forfeiture of their ability to challenge the IRS in tax court.
Under the new law, the IRS must:
- notify taxpayers of the specific reasoning for the alleged math errors on their tax returns;
- show the mathematical changes made to their tax returns; and
- inform taxpayers of the 60-day abatement period.
However, if the taxpayer does not request an abatement within 60 days of receiving the notice, the adjustment will become final.
The new law also creates a pilot program that:
- sends trial notices through either certified mail or registered mail to impacted taxpayers; and
- requires Congress to report on the results of the pilot program.
The National Taxpayer Advocate applauded Congress for enacting the measure, calling it a "long-overdue reform that strengthens taxpayer rights, improves transparency, and ensures fairness in IRS communications."
Report from the IBFD Newsroom. Follow our reporting on this via our daily Tax News Service (subscribers only).