In Vaud at least, the ECA automatically send you a bill each year. It will be the same amount unless you notify them to increase cover. I'm sure premiums must go up every once in a while but the hikes aren't that big - you certainly won't get a bad surprise like health premiums. Actually its one of the cheapest insurances around, I guess because it's compulsory and there are lots of subscribers. In Vaud it's compulsory to insure the building with the ECA. You can insure the contents against fire with a private insurer but my private insurance company told me that it's much cheaper to insure household contents against fire risk with ECA than with them.