The NCUA is amending its regulations governing a federal credit union's (FCU) authority to act as trustee or custodian to authorize FCUs to serve as trustee or custodian for Health Savings Accounts (HSA). The NCUA is issuing this final rule so that FCUs and their members can take advantage of the authority granted in the Medicare Prescription Drug, Improvement and Modernization Act of 2003 (Medicare Act). The Medicare Act authorizes the establishment of HSAs by individuals who obtain a qualifying high deductible health plan and specifies that an HSA may be established and maintained at an FCU. The final rule also amends NCUA's incidental powers regulation to include trustee or custodial services for HSAs as a pre-approved activity.