10 Things Everyone Should Know Before Enrolling in Medicare

10 Essential Things to Know About Enrolling in Medicare

Planning your Medicare enrollment? Understanding the basics of Medicare — including Parts A, B, D, and Medigap — can help you avoid costly mistakes. Whether you’re nearing age 65 or assisting a loved one, below are ten key points to help get you started. (This list is by no means exhaustive, but it’s a great place to begin.)

1. Medicare Part A Is Usually Free — But You Still Need to Enroll

For most Americans, Medicare Part A (hospital coverage) is premium-free. However, unless you’ve been receiving Social Security benefits for at least four months, you’ll need to proactively enroll when you’re eligible.

💡 Important: Once you’re enrolled in either Medicare Part A or Part B, you are no longer eligible to contribute to a Health Savings Account (HSA) — even if you keep your employer health plan.

2. Medicare Part B Premiums Depend on Income

The monthly premium for Medicare Part B (outpatient care) is often lower than what employees pay for workplace insurance. However, if your income exceeds $106,000 (individual) or $212,000 (couple) in 2025 or $109,000 (individual) or $218,000 (couple) in 2026, you’ll pay a higher premium due to IRMAA — the Income-Related Monthly Adjustment Amount.

3. Don’t Delay Prescription Coverage (Part D)

It’s essential to have creditable prescription drug coverage once you turn 65.If your employer plan does not include creditable drug coverage, you should enroll in Medicare Part D to avoid a permanent penalty.

⏳ The penalty equals 1% of the national base premium for each month you go without creditable coverage — and it never goes away.

4. Medicare Advantage and Medigap Are Not the Same

You’ve probably seen the commercials for “free” or “low-cost” Medicare Advantage plans — but these differ significantly from Medigap (Medicare Supplement) coverage.

• Medicare Advantage (Part C): Offered by private insurers and limited to their provider networks.

• Medigap: Works alongside Original Medicare and covers care from any provider who accepts Medicare.

Talk to a trusted, knowledgeable agent to determine which option fits your needs best. (Full disclosure: I’m not a big Medicare Advantage fan.)

5. Medicare + Medigap Often Provides Better Coverage

Many people are surprised to learn that the combination of Medicare and a Medigap plan can offer more comprehensive coverage and lower out-of-pocket costs than many employer-sponsored health plans.

6. You’ll Need Your Medicare ID Number First

Before applying for a Medigap or Medicare Advantage plan, you must have your Medicare ID number. Your Medicare card typically arrives about two weeks after you apply — so plan ahead.

7. Don’t Miss the Medigap Open Enrollment Window

There’s a six-month window that begins the first month you are both 65 and enrolled in Medicare Part B. During this time, insurers must offer any Medigap plan available in your state — without health screening or denial due to pre-existing conditions. After that six-month period, you may be subject to medical underwriting.

Medicare Advantage plans, on the other hand, can be joined or changed each year during the Annual Election Period (October 15–December 7).

8. Apply for Medicare at the Social Security Website

To apply for Medicare, go to the Social Security Administration’s website, not Medicare’s:👉 www.ssa.gov

9. You Can Apply by Phone or In Person

You can also apply at your local Social Security office or by calling 1-800-772-1213.Hold times can be lengthy, but if you’re close to your coverage start date, the phone option may be your fastest route.

10. Access Your Medicare Number Online

After submitting your application, your Medicare card usually arrives by mail within two weeks. However, you can often find your Medicare ID number sooner by creating an account at👉 www.mymedicare.gov

Bonus Tip: In a Rush? Try Enrolling by Phone

If you’re short on time, applying by phone can sometimes get you your Medicare number faster — just be prepared for long hold times and have any required documents ready to upload.

Of course, it’s always best to plan ahead — but if things happen last minute, this option can help.

Final Thoughts

Understanding Medicare doesn’t have to be overwhelming. The key is starting early, knowing your deadlines, and getting reliable advice.

Even a little preparation can prevent costly mistakes and ensure you get the coverage that fits your needs and budget.

About the Author

Laurie Dawson is a licensed insurance professional with over three decades of experience helping clients transition to Medicare. She is the owner of Treaster, Dawson & Associates, Inc., an employee benefit and HR consulting firm based in Peoria, Arizona.