When you have Medicare there are only a few periods that you have guaranteed issue rights for Medigap insurance. The first period that you have guaranteed issue rights for Medigap policies is when you first become eligible for Medicare. You have 6 months from the time you are eligible and purchase Medicare part B to enroll into a Medigap policy without underwriting issues. The second time that you have guaranteed issue rights for Medigap insurance is if you no longer have a Medicare Advantage plan. If you cancel our Medicare Advantage plan or the company no longer issues your policy you have 63 days from the last day of service to enroll risk free into a Medigap policy. However, you only have this right if you switch to regular Medicare and not another Medicare Advantage plan.
You will also have rights during your trial period with Medicare Advantage. If, during that trial period you change your mind and decide on regular Medicare you can purchase Medigap insurance without penalty. Due to the economy, many companies have gone out of business in the last few years. If you loose your coverage due to a company going bankrupt or closing you have guaranteed issue rights. Finally, if you were deceived by a Medigap provider who did not pay claims that they said they would or provide coverage you have protected rights. With this last scenario however, you will need to keep all the documents to prove that this happened.
States have the right to enforce certain aspects of insurance law, including those associate with Medicare. If your state offers open enrollment it is assumable that you will be offered the same protections as if you were initially applying for Medigap coverage.