The 6ft 4in, 115kg flanker – who has previously represented Jersey Reds – joined Edinburgh from Bristol Bears ahead of the 2019/20 season following two years at Ashton Gate.
Haining joined Bristol from Jersey Reds at the beginning of the 2017/18 season, having been one of the Channel Islanders’ standout performers in the English Championship.
In his first year in the West Country, the back-row played a pivotal role in helping Bristol to an immediate return to the Premiership.
Haining scored one try in nine appearances during the 2017/18 campaign as the Ashton Gate outfit finished as league champions.
Haining scored eight tries in 33 appearances during his two seasons in Bristol.
Date of birth: 01 September 1990