Building Complete Coverage

First Things First

You must be enrolled in Original Medicare through the Social Security Administration before you can start building on your coverage. You can do this by:


Download a free copy of Alight's guide to understanding Medicare.
Medicare Guide This guide can help you understand your Medicare options, make a well-informed coverage decision and enroll in a plan.


For even more information, the Centers for Medicare & Medicaid Services (CMS) offer a "Medicare & You" handbook.

Download Medicare & You

Original Medicare Basics

Original Medicare is a low-cost government insurance program that guarantees access to health insurance for Americans age 65 and older and younger people with certain medical disabilities. It pays for many health care expenses but not all. Medicare covers its share of an approved amount and you pay the rest through deductibles and coinsurance. Original Medicare is made up of two parts:

Part A:Hospital insurance which helps cover inpatient care in hospitals and skilled nursing facilities, hospice care, and home health care. Most people do not pay a monthly premium for Part A.

Part B:Medical insurance which helps cover medically necessary doctor services and visits, lab tests, outpatient care, durable medical equipment and supplies, ambulance services, and preventative care. Part B carries a monthly premium.

Your options for more comprehensive coverage

Private insurance companies partner with Alight Retiree Health Solutions to offer plans with monthly premiums to help cover costs that Original Medicare does not. Instead of paying doctors and hospitals directly, the government pays these private insurers to administer your plan. These options cover all or part of the deductible for Original Medicare Part A, as well as Part B coinsurance and deductibles, and must offer all the benefits and services covered under Original Medicare. Some plans may include additional benefits such as prescription drug coverage, routine dental services, or vision care.

Use the Plan Type Selector to help simplify coverage options.

Side-by-Side Comparisions of The Most Complete Options



Medicare Advantage Bundled With Prescription Drug


Medicare Supplement (Medigap) Plus Prescription Drug

Your Choices

The doctors and hospitals are part of a provider network (HMO or PPO) so you need to be sure your providers are included. With a PPO, you get an extended network but cost is higher.

You can use any provider that accepts Medicare. Cost is the same for all providers.

Out-of-Pocket Costs

Monthly premiums are typically lower, leading to lower total out-of-pocket cost if you don't frequently use medical services. If you do have higher usage, costs can vary for expected OR unexpected services.

Monthly premiums are typically higher, however other out-of-pocket costs are limited. Monthly costs are more dependable.

We recommend that you compare the total estimated out-of-pocket cost between MAPD and MEDIGAP + Part D to see whether the difference impacts you.

Option 1

Medicare Advantage (Part C) Bundled With Prescription Drug (Part D) = MAPD


Original Medicare Insurance


1 Or 2

Medicare Advantage bundled with a Prescription Drug Plan

Medicare Supplement Plan

Medical Coverage

Prescription Drug Plan

Prescription Coverage


Bundles Part C; D Plans into a single complete plan

Part C, also known as Medicare Advantage (MA)*: Network-based like an HMO or PPO, these plans combine all the benefits covered under Original Medicare into one policy, which may offer greater financial protection with a maximum out-of-pocket limit. 

Part D: Prescription Drug Plans help pay for medications you may need.

Why it makes sense:With a select provider network to contain costs (be sure your doctors and hospitals are in the carrier’s network), Medicare Advantage bundled with a built-in Prescription Drug Plan (MAPD) covers more than Original Medicare and is a more comprehensive plan option. Plus, many Medicare Advantage plans offer additional hearing, vision, or dental benefits. This combination may reduce or limit out-of-pocket medical costs, and premiums are generally lower than Medicare Supplement (Medigap) options.

Considerations:Medicare Advantage plans are less predictable from a monthly out-of-pocket perspective because you pay for services if and when you use them.

What is a Medicare Advantage (Part C / MA) Plan?

Medicare Advantage (Part C or MA) Plans are offered by private insurance companies through Alight Retiree Health Solutions and are approved by Medicare. If you join a Medicare Advantage Plan, you still have Original Medicare (Part A and Part B), but the insurance company is responsible for coordinating your care and paying claims.

Most Medicare Advantage plans have a Prescription Drug Plan (Part D) built in (MAPD). Always make sure your medications are listed in the formulary (a list of covered prescription drugs).

With Medicare Advantage, you are always insured for emergency and urgent care. Additional coverage for vision, hearing and/or dental may be available at an additional cost.

While you still have to pay your Part B premium, Medicare Advantage Plans typically have low or $0 monthly premiums. However, your costs will include copayments, deductibles, and coinsurance. Your annual out-of-pocket costs will vary depending on which plan you choose. All your coverage is combined into a single plan, with a single ID card, and one bill to pay.

Because these plans are network based (HMO and PPO), check to make sure your preferred doctors, hospitals, and specialists are included in the provider network.

When can you join a Medicare Advantage Plan?

Initial Enrollment: You have a 7-month period during initial enrollment. You can join 3 months before the month you turn 65, the month you turn 65, and up to 3 months after the month you turn 65.


If You Are Disabled: You can join during the 7-month period that begins 3 months before your 25th month of disability and ends 3 months after your 25th month of disability.

Annual Enrollment Period Between October 15 and December 7: Anyone with Medicare can join, switch, or drop a Medicare Advantage plan.

Special Enrollment: In certain situations, you may be able to join, switch, or drop a Medicare Advantage plan. Those special circumstances include a move out of your plan’s service area or you lose your current coverage.

Option 2

Medicare Supplement (Medigap) Plus Prescription Drug = MEDIGAP + PART D


Original Medicare Insurance


1 Or 2

Medicare Advantage bundled with a Prescription Drug Plan

Medicare Supplement Plan

Medical Coverage

Prescription Drug Plan

Prescription Coverage


Builds comprehensive coverage for remaining coverage needs after Original Medicare

Medicare Supplement, also known as Medigap*: Pays some of the health care costs that Original Medicare doesn’t cover, like copayments, coinsurance, and deductibles for Medicare-approved expenses.

Part D: Prescription Drug Plans help pay for medications you may need.

Why it makes sense: Medicare Supplement (Medigap) pays secondary to Original Medicare and is designed to help cover the costs that remain after approved Parts A and B have paid. These plans give you flexibility when choosing your doctors — you can go to any doctor or hospital that accepts Medicare — and monthly out-of-pocket costs are more predictable.

Considerations: Premiums and total out-of-pocket costs can be higher than Medicare Advantage.

alert-copy.png Plans C and F are only available if you were Medicare eligible before January 1, 2020. Other Medicare Supplement plans are available if you became eligible after that date.

Under the Medicare Access and CHIP Reauthorization Act (MACRA), Plans C and F will soon be replaced by new plans that do not cover the Part B deductible. This change will not affect those who are already enrolled in Plans C and F, but premiums may be higher to cover the cost of the Part B deductible.

*You cannot have Medicare Advantage and Medicare Supplement at the same time.

What is a Medicare Supplement (Medigap) Plan?

Medicare Supplement insurance is designed to fill gaps in costs for Medicare-approved expenses that Medicare Parts A and B do not cover. While there are a number of different Medicare Supplement options offered by private insurance companies through Alight Retiree Health Solutions, benefits are standardized in each state.

Medicare Supplement plans do not include prescription drug coverage, so you should consider enrolling in a Prescription Drug plan (Part D) as well.

For all states except Massachusetts, Minnesota, and Wisconsin, the chart below summarizes what each standardized Medicare Supplement plan (A-N) covers. With Plan F, you only pay the monthly premium and pay nothing additional for a Medicare-covered procedure when you see a doctor or go to a hospital that accepts Medicare.

Note: Plans C and F aren’t available to people newly eligible for Medicare on or after January 1, 2020. If you were eligible before this date, or if you already have or were covered by Plan C or F (or the Plan F high deductible version) before January 1, 2020, you can keep your plan if you wish.

Although Medicare Supplement offers standardized benefit packages, insurance companies set their own monthly premiums, so you need to compare prices among your options.

Checkmarks indicate plans that pay 100% of the benefit cost.

Medicare Supplement Plans

Medigap Benefits A B C D F1 G1 K2 L2 M N3
  50% 75% 50%
    50% 75%
50% 75%
50% 75% 3
50% 75%
    80% 80% 80% 80%     80% 80%

When can you join a Medicare Supplement (Medigap) Plan?

Medigap Open Enrollment: This 6-month period begins on the first day of the month in which you’re 65 or older and enrolled in Part B. (Some states have additional Open Enrollment Periods.) After this enrollment period, your option to buy a Medigap policy may be limited and may cost more.

  • If you delay enrolling in Part B because you have group health coverage based on your (or your spouse’s) current employment, your Medigap Open Enrollment Period won’t start until you sign up for Part B.
  • Some states require Medigap insurance companies to sell Medigap policies to people under 65.

Outside Open Enrollment: If you apply for Medigap coverage after Open Enrollment, there's no guarantee of acceptance unless you meet the medical underwriting requirements or are eligible because of a special situation.

Alternate Option

Original Medicare (Parts A and B) plus a Prescription Drug Plan (Part D)


Original Medicare Insurance


1 Or 2

Medicare Advantage bundled with a Prescription Drug Plan

Medicare Supplement Plan

Medical Coverage

Prescription Drug Plan

Prescription Coverage


Protection from the high cost of prescription drugs outside of Original Medicare

Why it makes sense: Original Medicare (Parts A and B) does not include prescription drug coverage, so this option adds a stand-alone prescription drug plan (Part D).

Considerations: Parts A and B only cover inpatient and basic outpatient services, leaving Medicare beneficiaries to pay the full cost of anything not completely covered.