Creditable coverage is used in two different ways. In general, it is coverage that gives you the right to buy or switch health insurance coverage without penalty, restriction, or waiting period. Different types of health insurance have different creditable coverage requirements.

For Medigap policies, certain health insurance coverage you had within 63 days of securing a new policy can be used to shorten the waiting period for pre-existing conditions. This type of coverage that shortens the waiting period would be called creditable coverage. For Part D, creditable coverage is prescription drug coverage that is evaluated by an actuary and determined to be as good as or better than the basic Part D benefit. If you have creditable drug coverage, you can delay enrollment without penalty. Medicare Part A and Part B enrollment is NOT affected by prior creditable coverage.