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Medicare Part A, B, C and D: What’s the Difference?

Selecting a Medicare plan can be overwhelming. Understand which plans cover which services so you can make the best choice for you.

Open enrollment happens every year from the middle of October to the middle of December. It is the period of time when you can make changes to your Medicare coverage. You can enroll in a new Medicare prescription drug plan, switch from Original Medicare to a Medicare Advantage plan (and vice versa) or change Medicare Advantage plans.

When you’re first selecting a Medicare plan, you may be faced with an overwhelming number of choices. One of the most challenging parts of understanding Medicare is how the different parts fit together.

This article describes the differences between Original Medicare (Parts A and B) and Medicare Advantage (Part C). It also explains how Part D fits into the different plans. You’ll also learn what else to keep in mind as you are picking a plan.

Original Medicare

Original Medicare (sometimes called Traditional Medicare) is insurance administered by the federal government. It consists of Part A, which covers hospital services, and Part B, which is medical insurance and covers expenses like doctor appointments, laboratory tests and X-rays.

If you have Original Medicare, you can enroll in other plans for additional coverage. You can add a Part D plan to cover prescription drugs. You can also select a Medicare Supplement Insurance (Medigap) plan, which helps pay for health care costs such as co-payments and coinsurance. You must have Medicare Part A and Part B in order to purchase a Medigap plan.

The Medigap Open Enrollment Period is a 6-month period which automatically starts the month you turn 65 and enrolled in Medicare Part B. Learn more about Medigap enrollment

Tip: If you have a chronic disease like psoriasis or psoriatic arthritis, it’s generally a good idea to add a prescription drug plan and a Medigap plan to make sure that all your health care costs are covered as fully as possible.

Medicare Advantage

Another option is to choose a Medicare Advantage plan (sometimes called Medicare Part C). Most people will have to sign up for Medicare Part A and/or Part B unless they are already getting benefits from Social Security or a certain disability benefit. With Medicare Advantage, you’ll still pay a premium for Medicare Part B, but all your benefits will be bundled under a single plan from a private insurance company. Medicare Advantage Plans may also offer prescription drug coverage.

Medicare Advantage plans are administered by private insurance companies that contract with the federal government.

Pros: Medicare Advantage plans are more popular than ever. For many, the option of having a single plan that covers all components of your health plan feels familiar and easy. Medicare Advantage is most similar to the benefits structure you may have received through an employer. While Medicare Advantage plans vary in terms of price and benefits, many offer additional coverage like vision and dental.

Cons: Keep in mind that if you have a Medicare Advantage plan, you may need to get a referral from your primary care provider to see a specialist, like a dermatologist or rheumatologist. If you have a Medicare Advantage plan, you may be required to see health care providers that are in-network, which means that a more limited number of specialists may be available to you.

Choosing a Plan

As you can see, there’s a lot to keep in mind when it comes to picking a plan. The right choice for you will depend on your whole health picture, the medications that you take on a regular basis and other factors.

The Medicare Plan Finder is an excellent resource to explore plan options in your area. You can use the plan finder to look at Original Medicare plan combinations, with supplemental coverage and a prescription drug plan. You can also compare your existing plan with other options. The plan finder will provide an estimate of your annual costs for each of your plan options, including premiums and drug costs.

Get Support While Shopping for a Plan

The NPF Patient Navigation Center is here to help. Request a free resource to learn more about selecting a plan.

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