<Tr> <Td_colspan="2"> ← Previous Season 11 Next → Season 13 </Td> </Tr> <Tr> <Td_colspan="2"> List of It's Always Sunny in Philadelphia episodes </Td> </Tr> <P> The twelfth season of the American comedy television series It's Always Sunny in Philadelphia premiered on FXX on January 4, 2017 . The season consists of 10 episodes and concluded on March 8, 2017 . </P> <Ul> <Li> Charlie Day as Charlie Kelly </Li> <Li> Glenn Howerton as Dennis Reynolds </Li> <Li> Rob McElhenney as Mac </Li> <Li> Kaitlin Olson as Dee Reynolds </Li> <Li> Danny DeVito as Frank Reynolds </Li> </Ul>

When does season 12 of it's always sunny start