It depends on the altitude/orbital height. Some are made to come down after only 5 years, I think most are restricted to no more than 25 years and head for a 20

It depends on the altitude/orbital height. Some are made to come down after only 5 years, I think most are restricted to no more than 25 years and head for a 20 year target. Of course just a small amount of on-board propellant could extend the time further boosting it a bit after a few years of drag.