The Expanding Support for Living Donors Act expands the federal Living Organ Donation Reimbursement Program to help living organ donors cover their donation-related expenses. The bill increases the maximum reimbursement from current levels to $10,000 in fiscal year 2027, with automatic adjustments for inflation in subsequent years, and allows donors with household incomes up to 700 percent of the federal poverty line to qualify for assistance regardless of income limits. The legislation requires the Department of Health and Human Services to submit detailed annual reports to Congress beginning in 2027, tracking program participation, reimbursement amounts, donation outcomes, and whether current funding is adequate to cover all donors' qualifying expenses. Additionally, the bill directs the Government Accountability Office to study within one year whether Medicare could use its existing authority to reimburse organ donation costs. Funding for the program is authorized through fiscal year 2037, replacing the previous authorization that expired in 2009.