If a person missing enrolling in a Medicare program, during open enrollment, there is a enrollment known as General Enrollment Period.
General Enrollment Periods runs from January 1st to March 31st every year. However, if you wait for this enrollment it may lead to lifetime premium charges for late Part B Enrollment, that could cost a person thousands of dollars and your Medical coverage will not begin until July.
If you miss Medigap Enrollment, which begins six after your turn 65 and are enrolled in Part B. Medigap policy, insurers may not be required to sell you a plan. They also may be allowed to charge you more money.
Note: Medigap polices might not be allowed to sold to those who are enrolled in Medicare Advantage plans.