Medicare Parts A and B (sometimes called "Original Medicare") pays for many, but not all, health care services and supplies. A Medicare Supplement Insurance plan, sold by private insurance companies, may help pay some of the health care costs that Medicare Parts A and B don't pay such as copayments, coinsurance and deductibles. Some Medicare Supplement Insurance plans offer coverage for additional services such as medical care when you travel outside the U.S.
If you have Original Medicare Parts A and B and you buy a Medicare Supplement Insurance plan, both will pay their share of Medicare-approved amounts for covered health care services.
Every Medicare Supplement Insurance plan must follow Federal and state laws designed to protect you and it must clearly be identified as "Medicare Supplement Insurance." Insurance companies can only sell you a "standardized" Medicare Supplement policy identified in most states by letters, Plans A-N. All plans offer the same basic benefits but some offer additional benefits, so you can choose which one best meets your needs.
Note: In Massachusetts, Minnesota and Wisconsin, Medicare Supplement plans are standardized in a different way
A Guide to Health Insurance for People with Medicare
This official government guide has important information about the following:
- What a Medicare Supplement Insurance policy is
- What Medicare Supplement policies cover
- Your rights to buy a Medicare Supplement insurance policy
- Steps to follow when you buy a Medicare Supplement insurance policy
- Switching Medicare Supplement policies
For Massachusetts Residents (PDF)
For Minnesota Residents (PDF)
For Wisconsin Residents (PDF)
For residents of all other states or territories (PDF)
How much does Medicare Supplement Insurance cost?
Insurance companies may charge different premiums for exactly the same Medicare Supplement coverage. As you shop for a Medicare Supplement policy, be sure you are comparing the same Medicare Supplement policy (for example, compare Plan A from one company with Plan A from another company.)
How do I enroll?
You can apply to buy a Medicare Supplement Insurance policy any time after you reach age 65 and join Medicare Part B. Medicare guarantees you the right to buy any Medicare Supplement Insurance policy available where you live during the six months after you turn 65 and enroll in Medicare Part B. This six-month period is called your open enrollment period. Some states have ongoing open enrollment. Also, there may be other situations during which you are guaranteed acceptance into certain Medicare supplement plans.
During this time, an insurer can't consider your medical history or current health when setting the plan's premium. However, they may be able to make you wait for six months before coverage begins if you have a pre-existing condition when you buy the plan. After your open enrollment period ends, insurers can refuse coverage or charge you a higher premium based on your health.
Each private insurance company that offers Medicare Supplement Insurance plans handles the enrollment process for its plans. You'll need to contact the company directly and ask how to enroll.
You can contact your state's State Health Insurance Assistance Program (SHIP) to get a list of plans offered in your state. offers access to one-on-one counseling, education programs and other assistance. State Health Insurance Assistance Programs are federally funded for people with Medicare and their families.
AARP endorses the AARP® Medicare Supplement Insurance Plans, insured by UnitedHealthcare Insurance Company (UnitedHealthcare Insurance Company of New York, Islandia, NY). UnitedHealthcare Insurance Company pays royalty fees to AARP for the use of its intellectual property. These fees are used for the general purposes of AARP. AARP and its affiliates are not insurers.
AARP does not employ or endorse agents, brokers or producers.
Insured by UnitedHealthcare Insurance Company, Horsham, PA (UnitedHealthcare Insurance Company of New York, Islandia, NY for New York residents). Policy form No. GRP 79171 GPS-1 (G-36000-4). In some states plans may be available to persons under age 65 who are eligible for Medicare by reason of disability or End-Stage Renal Disease.
You must be an AARP member to enroll in an AARP Medicare Supplement Plan.
Not connected with or endorsed by the U.S. Government or the federal Medicare program.
This is a solicitation of insurance. A licensed insurance agent/producer may contact you.
Call a licensed insurance agent/producer at 1-866-408-5545 (TTY 711) to receive complete information including benefits, costs, eligibility requirements, exclusions and limitations.