Medicare provides healthcare coverage for many Americans age 65 or older. As of August 2022, an estimated 64.5 million people were enrolled in Medicare parts A or B, while another 29.1 million had a private Medicare Advantage plan. The annual Medicare open enrollment period gives beneficiaries an opportunity to make changes in their coverage.

Knowing when the Medicare open enrollment window opens and closes is important for managing coverage from year to year.

Medicare Basics

Medicare is a federal program that offers healthcare coverage to seniors ages 65 and older and younger people with certain qualifying health conditions or disabilities. Separate parts of Medicare cover particular categories of healthcare services.

• Medicare Part A: Medicare Part A covers inpatient care in a hospital, skilled nursing facility or nursing home care that’s not required on a long-term basis, as well as hospice care and some home healthcare.
• Medicare Part B: Medicare Part B covers doctor visits and other outpatient services, as well as mental health care, ambulance transport, durable medical equipment, laboratory tests, and preventive screenings. Parts A and B are sometimes called original Medicare to distinguish them from privately administered Medicare Advantage plans.
• Medicare Advantage (Medicare Part C): Medicare Advantage plans are an alternative to original Medicare, offered by private insurance companies under Medicare guidelines. Participants typically have lower out-of-pocket costs but coverage is generally limited to network providers.
• Medicare Part D: Medicare Part D provides prescription drug coverage. You must have traditional Medicare coverage or a Medicare Advantage plan to enroll in Medicare Part D.
• Medigap: Medigap, or Medicare Supplement Insurance, is sold by private companies and pays some of the costs original Medicare doesn’t cover, including deductibles, coinsurance, and copays.

What Is Medicare Open Enrollment?

Medicare open enrollment is a designated window of time each year when individuals can make changes to their Medicare coverage.

Open enrollment is primarily for people who already have Medicare. New applicants should sign up during their initial enrollment period, which starts three months before they turn 65 and ends three months after the month when they turn 65. If they miss their initial enrollment period, they can sign up during open enrollment.

The fall open enrollment period for Medicare begins Oct. 15 and runs through Dec. 7 each year. This enrollment period is open to people who are covered by Medicare parts A or B.

A separate Medicare open enrollment period applies to people who are covered by a Medicare Advantage plan (Medicare Part C). The open enrollment period for Medicare Advantage plans runs from Jan. 1 to March 31 each year.

What Can You Change During Medicare Open Enrollment?

During the Medicare open enrollment period, you can make a number of changes to your existing coverage.

Specifically, you can use the Medicare open enrollment window to:

• Switch from Original Medicare (Parts A and/or B) to a Medicare Advantage plan (Medicare Part C)
• Switch from a Medicare Advantage plan to Original Medicare
• Change from your current Medicare Advantage plan to a different one
• Enroll in Medicare Part D prescription drug coverage
• Change your existing Medicare Part D drug coverage to a different plan
• Remove Medicare Part D coverage

If you have a Medicare Advantage plan, you can switch plans during the open enrollment period that extends from Jan. 1 to March 31. During this time, you could also opt to switch to Original Medicare and enroll in Medicare Part D.

Original Medicare vs. Medicare Advantage

One of the biggest questions you might have during open enrollment is whether it makes sense to choose original Medicare or a Medicare Advantage plan. Understanding the coverage options and costs can help with deciding which one makes more sense.

Here’s an overview of how the two compare.

When comparing Original Medicare and Medicare Advantage plans, it’s important to consider what’s covered and what you’ll pay. Most people do not pay a premium for Medicare Part A coverage. The standard monthly premium for Medicare Part B in 2023 is $164.90, though your premium may be higher based on income.

Both Parts A and B have deductibles and coinsurance. For Part A, they are as follows in 2023:

• $1,600 deductible for each benefit period
• Hospital days 1–60: $0 coinsurance for each benefit period
• Days 61–90: $400 coinsurance per day of each benefit period
• Days 91 and beyond: $800 co-insurance per “lifetime reserve day” (up to 60 days over lifetime)
• Beyond lifetime reserve days: patient pays all costs

The annual Medicare Part B deductible in 2023 is $226. After your deductible is met, you typically pay 20% of the Medicare-approved cost for most services, including doctor visits, outpatient therapy, and durable medical equipment.

What you’ll pay for a Medicare Advantage plan (Medicare Part C) will depend on the plan you choose. Medicare Advantage members remain responsible for paying their Medicare Part B premiums, though some plans may pay some or all of those on members’ behalf, a practice known in the industry as a Medicare giveback benefit.

Some Medicare Advantage plans may charge an additional monthly premium, but most don’t. The amounts you pay for deductibles, copayments, and coinsurance can also vary.

The price of Medicare Part D drug coverage depends on the plan and your income.

How to Choose a Medicare Advantage Plan

Medicare Advantage plans can be structured as:

Less common types of Medicare Advantage plans include HMO point of service plans and Medicare Medical Savings Account (MSA) plans. The key factors to consider when shopping for a Medicare Advantage plan are whether you’ll be able to see out-of-network providers, whether a referral is required to see a specialist, and how much you’ll pay in premiums as well as out-of-pocket costs

Medicare offers a plan finder tool that can help you compare Part C plans.

If You Miss Medicare Open Enrollment

If you miss the Medicare open enrollment period, you generally can’t make any changes to your coverage until the next one rolls around. There are, however, some exceptions. Special Enrollment Periods (SEPs) allow you to update your coverage under certain conditions. You may qualify if you:

• Relocate to an area that isn’t in your current plan’s service area
• Relocate to an area that offers new coverage options for your current plan
• Move into or out of a skilled nursing care facility
• Are released from prison
• Move back to the U.S. after living outside the country
• Leave coverage from an employer or COBRA (Consolidated Omnibus Budget Reconciliation Act) coverage
• Drop coverage under the Program of All-Inclusive Care for the Elderly
• Were but no longer are longer eligible for Medicaid
• Are enrolled in a Medicare Advantage plan or Part D plan that isn’t renewed
• Are eligible for both Medicaid and Medicare
• Qualify for the Extra Help program to pay for Medicare Part D prescription drug coverage

Those are just some of the situations in which you may be eligible to change your Medicare plan outside of the open enrollment period. You can learn more about special enrollment periods on the Medicare website.

During the Medicare open enrollment period, you can make changes to your coverage under Medicare parts A or B. Open enrollment runs from Oct. 15 to Dec. 7. A separate Medicare open enrollment period (Jan. 1 to March 31) applies to people in private Medicare Advantage plans. If you miss your open enrollment period, you’ll generally have to wait until the next year to make changes, although there are some exceptions.

Frequently Asked Questions

The Bottom Line

During the Medicare open enrollment period, you can make changes to your current Medicare coverage under parts A or B. Open enrollment runs from Oct. 15 to Dec. 7. A separate Medicare open enrollment period (Jan. 1 to March 31) applies to people in private Medicare Advantage plans. If you miss your open enrollment period, you’ll generally have to wait until the next year to make changes, although there are some exceptions.