Person of Interest season 5 is just about to finish on CBS and that is also the final season of the show. So far only the first four seasons can be seen on Netflix, with season 5 probably coming sometimes this autumn or maybe early 2017.
The first 3 seasons of Person of Interest can be seen on about 10 different Netflix regions including US Netflix, Norwegian Netflix and French Netflix. The fourth season is only available on two different regions at the moment and that is on US and on French Netflix, so if you want to watch all the four seasons then US Netflix is probably the best place to go.
If you are looking for season 5 which at the same time is the last season of Person of Interest then you might want to tune in to the CBS website and maybe CBS All Access where you can get access to all seasons of Person of Interest, including the last season. You can read more about watching Person of Interest on CBS (and on CBS All Access) on the following site.
Do not miss out on this chance to watch this fantastic TV series produced by CBS and now that season 5 is finished this is a great chance to start watching this TV series in a way where you know that you can actually watch it all the way till the end, making it easier to start (knowing that there is an end).