Social Security offices that accept applications for enrollment in and determine eligibility for the Medicare program. People who have signed up for early retirement benefits with the Social Security Administration or the Railroad Retirement Board receive their Medicare card in the mail automatically prior to their 65th birthday. Their application for retirement benefits serves as an application for Medicare Part A. Individuals who wait for full retirement age to sign up for SSA cash benefits will need to apply for Medicare approximately three months prior to their 65th birthday month at the Social Security office where they will do the paperwork and designate if they want Part A and/or B. They will get their Medicare card in the mail showing their enrollment (Part A and/or B) with an effective date, the first of their birthday month. These people are now enrolled in Original Medicare and can sign up with a supplement or Medicare Prescription Drug Plan (Part D), or have the option of receiving their Medicare benefits through a Medicare Advantage plan (HMOs, PPOs, special needs plans, private fee for service plans, Medicare savings account plans). If they choose to enroll in a Medicare Advantage plan, they will have to determine availability and which plan is best for them, and then will need to enroll directly with the plan of their choice. Information about Medicare Advantage plans is available in the Welcome to Medicare handbook people receive when they enroll, by calling 1-800-MEDICARE or by using the Plan Finder on the Medicare website.