As of October 2015, all 8 seasons are streaming on Netflix, obviously it's not "free" but that seems to be the closest you'll get.
youtube Full episodes all seasons: http://www.tvmuse.eu/tv-shows/Charmed_161/
TNT.com
you can watch it on youtube or hulu
you can watch them on youtube the only thing is the episodes are seperated into parts
everwood
TNT shows episodes in the weekday mornings.
You can go to TNT.com to watch full free episodes of Charmed.
You can watch Charmed on TNT.
Check the related link down below =)
youtube Full episodes all seasons: http://www.tvmuse.eu/tv-shows/Charmed_161/
TNT.com
yes you can at letmewatchthis.com or at netflix.com
You can see all charmed season 1-6 episodes on tudou.com HOwever, For season 7 and 8 you can use tvshack.net, surfthechannel.com, and youtube.com YOu won't find all episodes in one place.
you can watch it on youtube or hulu
everwood
Youtube
you can watch them on youtube the only thing is the episodes are seperated into parts