IRS Extending the Tax Assessment Period 

Background (Part 1) 

The Internal Revenue Service (Service) makes every effort to examine tax returns as soon as possible after they are filed. To ensure timely tax examinations, Congress has set deadlines for assessing taxes and making refunds or credit of tax. These deadlines are called “statutes of limitations.” Without statutes of limitations, a tax return could be examined and tax assessed, refunded, or credited at any time, regardless of when the return was filed. 

Assessment statutes of limitations generally limit the time the Service has to make tax assessments to within three years after a return is due or filed, whichever is later. The Service cannot assess additional tax after the time for assessment has expired under any statute of limitations (even if the Service discussed the need for a tax adjustment with you before the expiration). Statutes of limitations also limit the time you have to file a claim for credit or refund. The Service is legally prohibited from making a refund or credit for your claim if you file it after the time for filing has expired under the statute of limitations. Also, if you disagree with the return examination findings, we cannot provide you with an administrative appeal within the Service unless sufficient time remains on the statute of limitations. 

IRS Publication 1035 (TTT 03/09/2021)