This bill, titled the "Catch Up Act," amends the Internal Revenue Code of 1986 to modify how health savings account (HSA) contributions are calculated for married individuals with family coverage. Specifically, it revises Section 223(b)(5) to address the treatment of "additional contribution amounts," also known as catch-up contributions, which are available to individuals aged 55 and older. The current law divides the family HSA contribution limit between spouses. The key provision states that if both spouses have attained age 55 before the close of the taxable year, their combined additional catch-up contribution amounts will be included in the total HSA contribution limit that is then subject to division between them. This change allows both eligible spouses to fully utilize their catch-up contributions within the family's overall HSA limit. These amendments are scheduled to apply to taxable years beginning after December 31, 2025.