US SB655

Amends the Internal Revenue Code to disregard the period of detention when calculating tax deadlines for U.S. nationals unlawfully detained or held hostage abroad, including their spouses

Requires the Secretary of State and Attorney General to provide Treasury with annual lists of detained individuals beginning January 1, 2026, to identify those eligible for relief

Mandates automatic abatement and refund of any tax penalties, interest, or additional amounts assessed against individuals later determined to have been wrongfully detained

Establishes a refund program for eligible individuals (and their spouses/dependents) who paid tax penalties during the applicable period beginning January 1, 2021, with a 1-year extended window to claim refunds after notification

Applies to taxable years ending after enactment, with retroactive relief provisions for penalties paid on or before enactment