Filing bankruptcy invokes the automatic stay against creditors including the IRS. As you would expect, the Statute of Limitations (SOL) is extended during the period IRS is prevented from enforced collection. However, the SOL ”tack on” period is the time IRS was prevented from collection action plus six months.
Requesting a Collection Due Process (CDP) hearing also tolls or suspends the running of the Statute of Limitations on collection. However, the “tack on” period is only 30 days after the CDP is resolved. The suspension starts on the day IRS receives the CDP request and continues until withdrawn by the taxpayer or Appeal’s determination becomes final. Petitioning the Tax Court continues the suspension until the court’s decision becomes final, including any appeal to the Court of Appeals.
An Offer in Compromise (OIC) extends the collection statute during the time the OIC is pending until it is closed, including appeals, plus 30 days.
The collection SOL is suspended while a proposed Installment Agreement (IA) is pending and for 30 days following the rejection of a requested IA. The SOL is also suspended for 30 days after the termination of an IA.
Time out of country or in military service may also have SOL implications that must be considered when appropriate.