Turning 65 in Arizona: Here's What to Do, and When to Do It

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Most people approaching Medicare feel the same thing — not excitement, but a low-grade worry that they'll miss a deadline, make the wrong choice, or pay for a mistake for the rest of their lives. That feeling is completely understandable. Medicare has real deadlines, real penalties, and a few decisions that are genuinely hard to undo. What it doesn't have to be is confusing. This page walks you through the timeline in order, covers the situations that trip people up most, and tells you exactly where to get help when you're ready.

 

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Your Medicare Enrollment Timeline, Step by Step

Medicare doesn't come with a notification. Nobody sends you a letter three months before your birthday saying "here's what you need to do." That's why so many people miss windows they didn't know were open — or sign up for things they didn't need yet. The timeline below is the one we walk every new client through in their first appointment.

Three Months Before Your 65th Birthday

This is when your Initial Enrollment Period opens. The IEP is a seven-month window: the three months before your birthday month, your birthday month itself, and the three months after. Enrolling in Medicare Part A and Part B during the first three months of this window means your coverage begins on the first day of your birthday month. Wait until your birthday month or later, and your start date shifts — sometimes by several months.

 

What to do right now:

 

  • Confirm whether you're already enrolled in Part A. Most people who've paid into Social Security for at least 10 years are eligible for premium-free Part A and can enroll without waiting.
  • Decide whether to enroll in Part B now or delay it. If you have qualifying employer coverage, you may have the option to wait — more on that below.
  • Begin comparing Medicare Advantage plans and Medicare Supplement(Medigap) plans. This decision has long-term consequences, and it's worth understanding before your coverage begins, not after.
  • Contact Social Security to begin your Medicare enrollment if you haven't already started receiving Social Security retirement benefits. You can do this online at SSA.gov, by phone, or at your local Social Security office.

Your Birthday Month Through Three Months After

This is the continuation of your Initial Enrollment Period. The timing of your enrollment during this phase affects your coverage start date.

Your Coverage Start Date Depends on When You Enroll

If you enroll during your birthday month, coverage begins the first day of the following month. If you enroll in the first month after your birthday, coverage begins two months later. If you enroll in the second or third month after, coverage begins three months later. Enrolling early — in the three months before your birthday — gives you the cleanest start date and the most time to choose a plan without feeling rushed.

The Medigap Open Enrollment Window Is Separate — and It Matters

Your six-month Medigap open enrollment window begins the month you are both 65 and enrolled in Medicare Part B. This is not the same as your Initial Enrollment Period, and conflating the two is one of the most expensive mistakes people make in this process. During this six-month window, Arizona carriers cannot deny you a Medigap policy, charge you more because of health history, or require a waiting period for pre-existing conditions. Once this window closes, you can still apply for Medigap coverage — but carriers can underwrite you, which means health conditions can affect your eligibility and your premium. If Medigap is the direction you're leaning, this window is the time to act.

What If You're Still Working at 65?

This is the question we hear most often from people approaching Medicare, and it's one of the most poorly answered questions in this space. Here's the short version: if you have health coverage through your own employer or your spouse's employer, and that employer has 20 or more employees, you may be able to delay Medicare Part B without incurring a late enrollment penalty.

When Employer Coverage Qualifies as Creditable

Not all employer coverage delays the penalty. The key factors are the size of the employer and whether the coverage is considered "primary" — meaning it pays before Medicare would. If your employer has 20 or more employees and you're covered under their group health plan, Medicare becomes secondary, and you can delay Part B enrollment without penalty. When that employer coverage ends — because you retire, change jobs, or lose eligibility — you have an eight-month Special Enrollment Period to sign up for Part B without penalty. Do not wait for COBRA to end. The Special Enrollment Period clock starts when the employer coverage ends, not when COBRA ends.

When You Should Still Enroll in Part A Right Away

Even if you're delaying Part B, enrolling in premium-free Part A as soon as you're eligible is almost always the right move. Part A covers hospital inpatient care and has no premium for most people. The exception: if you're contributing to a Health Savings Account (HSA), enrolling in Part A makes you ineligible to continue making HSA contributions. If you're actively funding an HSA and want to continue doing so past 65, talk with us before you enroll in any part of Medicare.

If Your Employer Has Fewer Than 20 Employees

In this case, Medicare becomes primary — meaning it pays first, and your employer plan pays second. Delaying Part B in this situation can leave you with significant uncovered costs. Most people in this scenario should enroll in Part B on time, even if they're still working.

Medicare Eligibility Beyond Age 65

Age 65 is the most common path to Medicare, but it's not the only one. You may be eligible for Medicare before 65 if:

 

  • You've received Social Security Disability Insurance (SSDI) benefits for 24 consecutive months.
  • You have End-Stage Renal Disease (ESRD), which qualifies you for Medicare at any age regardless of disability status.
  • You have ALS (amyotrophic lateral sclerosis), which triggers Medicare eligibility immediately upon approval for SSDI — the 24-month waiting period does not apply.

 

If you or someone in your family is navigating Medicare before 65, the rules around enrollment, plan options, and Medigap availability differ from the standard age-65 path.

Common Questions About Turning 65 and Medicare

  • When do I sign up for Medicare if I'm turning 65 in Arizona?

    Your Initial Enrollment Period opens three months before the month you turn 65. Enrolling during those first three months gives you a coverage start date of the first day of your birthday month. You have until three months after your birthday month to complete enrollment, but waiting pushes your start date back. For most people, earlier in the window is better.

  • Do I have to take Medicare if I'm still working?

    Not necessarily. If you have health coverage through an employer with 20 or more employees — your own or a spouse's — you may be able to delay Medicare Part B without penalty. Part A is generally worth enrolling in right away unless you're actively contributing to an HSA. The answer depends on your specific coverage, so it's worth checking before you assume either way.

  • What happens if I miss my Medicare enrollment period?

    If you miss your Initial Enrollment Period without a qualifying reason, you'll face permanent late enrollment penalties on Part B and Part D. You'll also need to wait for the General Enrollment Period (January 1 – March 31) to sign up, with coverage beginning July 1. Missing the Medigap open enrollment window means future applications are subject to medical underwriting. These are the decisions where getting the timing right matters most.

  • What do I need to do three months before I turn 65?

    Three months out, your Initial Enrollment Period has just opened. Start by confirming your Part A eligibility, determining whether you can or should delay Part B, and beginning to compare plan options. If you're enrolling in Part B, contact Social Security to start the process. If you're considering Medigap, remember that your open enrollment window begins when you're both 65 and enrolled in Part B — so knowing that start date matters.

  • How do I enroll in Medicare Part B?

    You enroll in Part B through the Social Security Administration, not directly through Medicare. You can apply online at SSA.gov, call Social Security at 1-800-772-1213 (TTY: 1-800-325-0778), or visit a local Social Security office. If you're already receiving Social Security retirement benefits when you turn 65, you're typically enrolled in Parts A and B automatically and will receive your Medicare card in the mail.