Phönix C.I aircraft built by Phönix were serialled from Phönix C.I 121.01 to Phönix C.I 121.160 and Phönix C.I aircraft ordered from Lloyd were allocated serials from Phönix C.I 49.01 to Phönix C.I 49.100. Some 80 aircraft ordered from UFAG were not assigned serial numbers, probably due to production being interrupted by the Armistice and 225 more were ordered but not built.