Medicare Supplement insurance, also called Medigap, is private coverage you buy on top of Original Medicare to pay the cost-sharing it leaves to you. In my work reviewing plans from hundreds of carriers, I've found most buyers don't realize how large those leftover costs can be until they're already in the hospital.
The federal government standardizes all 10 plan types. Plan G from Aetna and Plan G from Mutual of Omaha cover the same benefits in every state. Our analysis focuses on the premium side, where identical Plan G coverage can cost $100 or more per month less at one company than another.



