When Can I Apply For Medigap? 
You can apply for a Medigap plan at any point during the year - Medigap plans are not subjected to the same restrictions as Parts C & D of Medicare . You can complete an application up to 3 months in advance of the proposed effective date for the coverage - please note , you have to have both Medicare Part A & Part B to buy a Medigap plan . For example , if your effective date is April 1st , you could apply as early as January 1st . And vice versa - you can set the effective date up to 3 months later from the application date -LRB- most will set it up for the 1st of the following month though -RRB- . The effective date for your Medicare Part B coverage is also the starting point for your initial open enrollment period - a 6-month window where you can buy any Medigap plan from any carrier with NO medical underwriting -LRB- this is the best time to buy a Medigap plan -RRB- . Beyond this window , you will be required to answer health questions on the applications and go through medical underwriting -LRB- there are no exams though -RRB- , unless you have a qualifying event for a guaranteed-issue right . You should work through a broker who can shop the case for you and find you the desired Medigap plan at the lowest possible cost . It 's important to review your Medigap plan every year to see if a lower rate is available after the initial rate lock guarantee expires and/or when you have a rate increase . The benefits of a Medigap plan do not change from company to company - they are exactly the same . A plan F from one company features the exact same benefits as a plan F from another company . I hope the information is helpful - please feel free to contact me for assistance with your Medigap coverage and if you have any other questions . Thanks very much . 