There is a birthday rule in California for Medicare supplement/medigap enrollees that allows for a special election period. If you find that the premium for your current medigap/Medicare supplement plan has become too expensive for you, there may be another carrier whose premium for the same plan you are currently on is lower. In addition, during this special election period, you may decide to change to a different medigap/Medicare supplement plan in addition to changing carrier.
The election period occurs within within the 30 days following your birthday, with the plan change becoming effective the 1st of the following month. This change is a guaranteed issue (no health history underwriting).
Medigap/Medicare supplement plans are defined by Medicare and cannot be changed by a carrier. Although another carrier can offer your same plan at different premium, the plan benefits will not differ by insurance companies since the benefits are assigned to the plans by Medicare.
Be aware, however, that if you decide to “go down the letters of the alphabet” i.e., from a Plan F to a Plan N, you will not be able to go back up the letters of the alphabet to a Plan F without undergoing health history underwriting and so may be declined.