Medicare Supplement Insurance, which is often sometimes referred to as MedSupp or Medigap, is an insurance policy for people who are receiving health insurance coverage through Medicare and who would like to have additional coverage. A Medicare Supplement Insurance lowers your out-of-pocket costs, and helps you afford better health care.

Medicare Supplement insurance covers the health care expenses that Medicare does not cover - those expenses that do not meet Medicare requirements, or any part of the cost of treatment that exceeds Medicare coverage limits. Such additional benefits include routine yearly check-ups, at-home recovery, the difference between your doctor's charge and Medicare's approved amount and prescription drugs, just to name a few. Do note that no Medicare Supplement Insurance will cover all gaps in Medicare costs.

Medicare Supplement Insurance is sold by private insurance companies. There are 10 standard Medicare Supplement Insurance plans - named A-J. The plan benefits are federally required to be standardized for all insurance companies. Each plan offers different benefits, fills different gaps in Medicare and varies in premium pricing. Some insurance companies offer a "high deductible option" on Medigap Plans F and J. Some states may impose requirements particular to the state. Regardless, all Medicare Supplement Insurance plans must cover certain basic benefits.

If you are enrolled in a Medicare + Choice Plan, or if you are eligible for Medicaid, the State and Federal Government program that pays for certain health services and nursing home care for older people with low incomes and limited assets, you may not need Medicare Supplement Insurance. To buy a Medicare Supplement Insurance policy, you must have either Medicare Part A or Part B.