I've been trying to figure out my insurance coverage since retiring in March. Things have gotten quite confusing. I am on Medicare A & B and when I retired I signed up for Plan F through Cigna. For 25 years I was with Cigna through Orange County and things were simple. All I had to do was sign on to Mycigna.com and all the bills, deductables and stuff was right there. In a matter of a few minutes I could figure it all out. I have been getting medical bills and EOB's that show what was paid and what I owe. My assumption was Plan F pays what medicare does not. Is that correct? I just want to make sure all the bills are being paid and I am not getting screwed. Can somebody explain how medicare plan F works and why I am getting these bills?