The 7-month Initial Enrollment Period
IEP usually starts 3 months before the month you turn 65, includes your birthday month, and ends 3 months after. If your birthday is the 1st of the month, Part A and Part B can start the first of the prior month. Confirm dates with Social Security. Use the eligibility calculator if you want a date sketch.
Before the window: Parts A and B
Most people enroll in Part A (hospital) and Part B (medical) first. If you or a spouse still works, employer size and whether coverage is creditable can change whether you delay Part B. Get that in writing from the benefits office. Do not guess from a friend’s situation.
During the window: drugs and the rest
Original Medicare does not include routine outpatient drugs. You generally add Part D or join a Medicare Advantage plan that includes drug coverage. Going 63 days or more without creditable drug coverage after you are eligible can add a late-enrollment penalty. Medigap, if you want it, has its own open-enrollment clock after Part B.
IEP is not AEP
Annual Enrollment (October 15 – December 7) is for people who already have Medicare and may change Advantage or Part D. Mixing those windows is a common source of stress. Confirm both on Medicare.gov.
Common questions
- Is turning 65 the same as Open Enrollment?
- No. Initial Enrollment is for people new to Medicare. Annual Enrollment (October 15–December 7) is a later window for people who already have Medicare.
- Where do I confirm my dates?
- Social Security and Medicare.gov. This website does not enroll you or set your start date.
2026 figures
Medicare eligibility date
See when Part A and Part B can start at 65, and your Initial Enrollment window.
Educational answers — not a plan recommendation.
Educational estimate using public 2026 CMS figures. Not a bill, not a determination, and not a plan recommendation. Confirm on Medicare.gov or with Social Security. We are not affiliated with or endorsed by the U.S. Government or the federal Medicare program.
We are not affiliated with or endorsed by the U.S. Government or the federal Medicare program. This page is general education. We do not offer every plan available in your area. Currently we represent 6 organizations which offer Medicare Advantage and Part D products in California. The number of products available to you depends on your ZIP code. For a complete list of options, visit Medicare.gov, call 1-800-MEDICARE (1-800-633-4227), TTY 711, or California HICAP at 1-800-434-0222.