Personally, we have the Canadian Pension Plans plus we have the Old Age Pension, which are considered income so we still have to file on those. I believe that the only time you don’t have to file is if you supremely leave Canada; if you renounce your citizenship, etc.
However, we only have to pay income tax when the money is earned in Canada. We’re paying Panamanian taxes on the money we make here, but not Canadian tax. In Canada you only can be taxed once on your income.
(Choosing at lot and home at Tucan Country Club and Resorts, Panama, pictured.)