Is Medigap Better Than Advantage? 
Each type has it 's pros and cons . Medigap plans -LRB- commonly known as Medicare supplement plans -RRB- work with Original Medicare -LRB- Parts A & B -RRB- to fill the `` gaps '' that it does n't cover . Original Medicare covers about 80 % of your healthcare expenses . A Medigap plan can cover a portion or all of the other 20 % , depending on which one you get . That 's a BIG pro . You also are n't restricted to networks , you do n't need referrals to see specialists , any doctor that accepts Medicare will accept the Medigap plan , you can apply for a different plan at any point throughout the year -LRB- if you want a different carrier or different benefits -RRB- , and they are guaranteed renewable ! The only con is that it typically costs more than an Advantage plan . Advantage plans can be a lot cheaper , but have more restrictions and limitations than a Medigap plan does . The big attraction with them is the cost factor as the premiums are very cheap and some plans even feature a $ 0 premium - they can also include drug coverage -LRB- you have to buy a stand-alone part D prescription drug plan if you want prescription coverage when you have a Medigap plan -RRB- . Some of the drawbacks are that you can have network restrictions , the plan coverage can change each year , your doctor can choose to no longer accept that specific plan , you 're locked in to that plan for a year and can only change it during the annual enrollment period -LRB- Oct 15-Dec 7 of each year -RRB- or if you qualify for a special enrollment period . Please note , regardless of which type of coverage , you must have both Part A & Part B and continue paying your Part B premiums -LRB- even though Advantage plans work in place of Original Medicare - Medigap plans work with Original Medicare -RRB- . 