My pre-paid tracfone has no fees. I purchased the phone ($14 w/20 free minutes from Sam's) and loaded the minutes. Every 90 days or so depending on the card, I load another phone card, and I have hundreds of minutes that roll over. They have much higher options like 50, 100, 500, and a 1000 minutes that carry the length of time between needing to add minutes up to a year. There, clear as mud.
Each company is a little different.
Disclaimer...Dh has a phone supplied from his office that is much cooler according to my ds.