Medicare (the Centers for Medicare & Medicaid Services) · Website: www.medicare.gov · Phone: 1-800-MEDICARE (1-800-633-4227) (TDD: 1-877-486-2048), 24 hours a day, 7 days a week.
Medicare Publications · A Guide to Health Insurance for People with Medicare · Medicare & You
U.S. Social Security Administration · Website: www.ssa.gov · Phone: 1-800-772-1213 (TDD: 1-800-325-0778). You can use the automated telephone services to get recorded information and conduct some business 24 hours a day. If needed, you can speak to a Social Security representative between 7am and 7pm, Monday through Friday.
Internal Revenue Service
Forms and Publications: