A benefits specialist in the HR dept. should know what your options are. Medicare Advantage programs are often "free", but the copays may ultimately equal more than the premiums for a supplement. You also may not have the access to healthcare options that you would prefer. I had a very good Blue Cross/blue shield plan through my employer prior to retirement. My employer paid 100% of the premiums. I went on medicare A and B 18 months ago, bought a supplement through AARP for about $350/month for wife and I. I paid way less for health care costs, including premiums, in the last 12 months than I did even with my premiums paid, in the 12 months prior to going on medicare plus supplement. Medicare parts A and B, and my supplement pay 100% of our healthcare costs, and we have had some significant expenses, although nothing critical, in the last couple years. My part D drug expenses are about the same as prior to medicare.