Verified answer

season 4 is currently airing in the uk- will most likely air in the usa in 2012 on SyFy

http://www.imdb.com/title/tt1199099/

http://www.bbc.co.uk/merlin/

http://www.syfy.com/merlin/

Season 4, interior the U. S. is commencing on the sixth January so which you're forward (in case you reside interior the U. S.). it has finished interior the united kingdom and season 5 filming will initiate in March to around July/August. Season 5 would be airing in around 9 months time. a protracted wait, i understand.