Published Aug 10, 2020
Updated Nov 6, 2025

Understanding Medicare and Your Options

Article at a glance

  • Original Medicare comes with two different parts: Part A (hospital insurance) and Part B (medical insurance). 

  • Medicare Advantage is often called Part C” because it combines Parts A, B, and D all in one plan and fills the coverage gaps associated with Original Medicare. 

  • If a patient qualifies for Medicaid, they are able to enroll in what is known as a dual eligibles” program combining Medicaid and Medicare. 

  • If you or your spouse are still working and/​or have insurance through an employer, you might not need to opt into Medicare just yet. 

Understanding Medicare and your options can be confusing, but it doesn’t have to be. This resource will explain everything you need to know about the basics of Medicare coverage choices, what Medicare pays, what certain Medicare plans cover, and more.

What is Medicare?

The Federal Medicare Program is a federal health insurance program instituted by the federal government that provides health coverage for adults over 65 and those under 65 with certain disabilities. The plan is funded by both the Social Security Administration and the Medicare taxes you pay on your income.

Many people today are working past 65, for various reasons. If this is you, you don’t need to sign up for Medicare, as long as you are under your employer’s group plan covering at least 20 employees. You can also opt-out of enrolling at 65 if your spouse is covered by their employer group plan as well.
 

Once you become Medicare-eligible, you can enroll in:
 

  • Original Medicare
  • Medicare Part D
  • A Medicare Advantage plan
  • Medicare Supplement plan

Note: Learn more about Medicare eligibility at this resource.
 

What Is Original Medicare?

Original Medicare includes both Parts A and Part B coverage, leaving the patient responsible to make up for any gaps in coverage and out-of-pocket costs. For example, Original Medicare doesn’t cover prescription drugs, so Original Medicare beneficiaries must enroll in a separate Medicare drug coverage (Part D) in addition to Medicare Parts A and B.

Medicare Part A

Part A, otherwise referred to as hospital insurance, is usually premium-free if you have worked for at least 10 years and paid into Medicare taxes. If these circumstances don’t apply to you, you can enroll in Part A with a monthly premium cost. 
 

Medicare Part A consists of coverage for services such as: 
 

  • Skilled nursing facilities
  • Hospital visits
  • Home healthcare
  • Hospice care

     

Medicare Costs of Part A

Part A is free to you if:
 

  • You currently receive retirement benefits from either Social Security or the Railroad Retirement Board
  • You’re eligible to get Social Security or Railroad Retirement Benefits but you have yet to file

If you’re under 65, you’re eligible to receive premium-free Part A if:
 

  • You have Social Security or Railroad Retirement Board disability benefits for 24 months
  • You have End-Stage Renal Disease and meet certain requirements

Note: If you must purchase Part A, you must also buy Part B simultaneously, which also comes with its own monthly premiums.

Medicare Part B

Part B, also known as medical insurance, usually carries a monthly premium. Social Security will typically send you sign-up instructions at the beginning of your initial enrollment period, three months before the month of your 65th birthday. 
 

Medicare Part B consists of coverage for the following services such as: 
 

  • Doctor visits
  • Preventative services
  • Ambulances
  • ER visits
  • Outpatient procedures
  • Durable medical equipment

Part B Premium

For 2023, a standard Part B premium will typically run $144.60 a month. This is usually drawn from Social Security or Railroad Retirement benefits. There are copays and deductibles with Part B, and individuals who earn more than $87,000 per year or $174,000 for couples, for their adjusted gross incomes, will pay more.
 

You’re not forced to sign up with Part B when you become Medicare eligible. However, if you wait it could cost you more in the end, due to late-enrollment penalties.

Part B Deductible:
 

  • Your deductible in 2023 is $226
  • You typically pay 20% of the Medicare-approved amount

Medicare Part D

In order to get health and drug coverage, someone must elect for Medicare Part D or enroll in a Medicare advantage plan part c plans that offers Medicare drug coverage. Part D prices vary by plan. The premiums start at $35 a month and go up from there. This is a separate Medicare drug plan that is optional, but useful when it comes to covering prescription costs. Usually, this plan is offered through private companies and may be included in a Medicare Advantage plan.

Note: While you may not be taking any prescription drugs when you become Medicare eligible, if you wait until after your Annual Enrollment Period, you will be penalized with a higher rate when you do finally enroll. 
 

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Medicare Advantage (Medicare Part C)

Medicare Advantage is considered managed care, as well as all-in-one insurance. This is because most Medicare Advantage plans combine Part A and B (what Original Medicare covers) along with Part D and additional benefits all in one plan. Most also offer additional benefits, such as hearing and dental services.
 

Medicare Advantage Additional Benefits:
 

  • Gym memberships
  • Dental care
  • Vision
  • Transportation to specialists
  • Podiatry

Medicare Advantage Cost

These services may come at little to no cost, with fixed copays, so you’ll know how much you need to pay before anything is done. Plus, these plans usually come with maximum out-of-pocket limits and premiums that never rise. Like other insurance plans, you will have to stay within your network, and coverage is offered through private insurance companies during your Medicare Open Enrollment Period.
 

Two women sitting and smiling on a park bench.

Dual Eligibles: Medicare + Medicaid

It is possible to have both Medicare and Medicaid services if you qualify. This means Medicare is your primary coverage and Medicaid becomes your secondary coverage. This is called​“dual eligible.” Having dual coverage generally will not cost you anything more and comes with additional benefits. Having both Medicare and Medicaid means you are covered for Part A, Part B, and Part D.

Dual Eligibles Additional Benefits:

  • Dental

  • Vision

  • Transportation

  • Over-the-counter drug benefits

  • And more

Dual Eligibles Cost

These plans are usually $0 per month with $0 copays. You must stay in the plan’s network, but people with Medicare and Medicaid are not restricted to Medicare’s open enrollment, so you can enroll in this plan or change plans quarterly.

Medicare Supplement Insurance

Another way of covering expenses Original Medicare doesn’t is through a MedSupp or Medigap plan. These supplement plans work with Medicare and generally pay 20% of the coinsurance and a large part of the Part A deductible. However, they are different from Medicare Advantage plans because of cost and what services they each provide.
 

  • Plans do not offer extra benefits besides what you already receive with Original Medicare
  • Plans do not cover Part D
  • Monthly premiums typically run $180 $500 per month
  • Your network will remain the same as your Medicare network
  • Enrollment happens any time of the year
  • If you sign up after you turn 65, any pre-existing conditions can factor into higher premiums and even being denied coverage

As of January 1, 2020, Medigap plans sold to new people with Medicare are no longer allowed to cover the Part B deductible. Due to this, Part C and Part F are not available to people new to Medicare starting January 1, 2020. If you currently have either of these two plans, or the high-deductible version of Plan F, or are covered by one of these plans before January 1, 2020, you will be allowed to keep your plan. In addition, if you were eligible for Medicare before January 1, 2020, but not yet enrolled, you may be able to buy one of these plans. 

Options Outside of Medicare

Many circumstances lead to the decision on whether you should enroll for Medicare benefits when you turn 65. However, here are some things to take into consideration when making this decision:
 

  • Are you still employed and covered by your employer’s group health plan?
  • Does that group health plan cover at least 20 employees?
  • Are you married to someone who is still working and covered by their employer’s group health plan that covers at least 20 employees?

If you answered yes to any of the above, it is not demanded of you to enroll in Medicare when you become Medicare eligible. However, there are certain things to take into account:
 

  • If you don’t fall into any of the above categories, you incur a yearly penalty for every year you didn’t have Medicare coverage
  • Medicare Part A can be used in conjunction with your employer’s group plan to help subsidize any out-of-pocket expenses
  • If you leave your employer during that time, you’ll get an 8‑month Special Enrollment Period to sign up for Medicare
  • Your 8‑months to find a Medicare plan begins one month after you leave your employer’s group plan, or one month after you separate from your employer, whichever happens first
  • If you sign up during this time, you won’t have to worry about premium surcharges for being late. The 8‑month Special Enrollment Period is also available if you’re delaying Part B enrollment if you’re covered under your spouse’s employee group plan.
     

It’s good to remember, even if you are satisfied with your current Medicare coverage, plans change and costs rise every year, so it’s worth it to look into your options and make sure you’re getting the most from your benefits.

A standing woman helps two sitting adults fill out paperwork.

How to enroll in Medicare

No matter what Medicare options work best for an individual, there are certain times when it’s better to enroll, both for initial enrollment and to change plans.

Initial enrollment is the three months before and after someone turns 65, the same year they start collecting social security. Often, it makes sense to research options, find a hospital that takes Medicare, and budget for Medicare costs before this period so enrollment goes as smoothly as possible. Initial enrollment is also the best time to join a separate Medicare drug insurance or Medigap plan.

Those who miss initial enrollment often face penalties and may experience a gap in their coverage. Sometimes, there are special enrollment periods for those who qualify.

If someone is unhappy with their plan and wants to switch, they can do so during the open enrollment period (from November 1st to January 15th). Medigap plans can be harder to purchase during this time period, but it’s easier to switch Medicare providers for Parts A and B. If prescriptions have changed, this is the time to switch Part D providers as well.

To enroll in Medicare, head over to the Medicare website. It’s important to enroll on Medicare.gov for original Medicare and on the insurance provider’s website for Medicare Advantage. Enrolling elsewhere may leave individuals open to scams or fraud.

Frequently Asked Questions

What are the 4 types of Medicare?

There are four lettered parts of Medicare. Part A is hospital insurance and Part B is medical insurance, both offered by the federal government. When these services are provided through a private company, they are considered Part C. Part D coverage is for prescription drugs. While optional, many find a part D drug plan useful.

How do I determine which Medicare plan is best for me?

There are many great Medicare options and the best one may vary depending on your healthcare needs, primary care doctor, and if you want additional benefits, such as vision, hearing, and dental. Fortunately, each state offers free counseling services through their government-funded SHIP offices. SHIP counselors can help find the coverage appropriate for the doctors offices you visit, your budget, and any other concerns.

What is the biggest disadvantage of a Medicare advantage plan?

The biggest disadvantage when you join a Medicare advantage plan is that the provider network is determined by the insurance company. Original Medicare is accepted anywhere in the U.S. with all doctors as in-network providers while Medicare Advantage plans have in-network and out-of-network providers. Coverage options also change every year so if on a Medicare Advantage plan, make sure to review your health care policy annually.

What are the parts of Medicare?

The main parts of Medicare are Part A and B. Part A covers inpatient costs and part B benefits cover health care costs associated with many preventive services. Medicare Part D is an optional plan that covers prescription drugs and certain other health care costs, like some durable medical equipment. There’s also Medicare Advantage which is when a private insurance provides a Medicare improved plan that covers part A and part B services. 

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