The veteran centre-back left the club to join Aston Villa at the end of last term, and the Italian has confessed that he attempted to keep him for another season.
"It was a big loss. A big loss. I tried to keep [Terry] for another season, but he wanted to play. He wanted to play and I understood this. I wish to him the best for him and his family," Conte told reporters during his pre-match press conference for Chelsea's Premier League clash with Crystal Palace.
"John Terry's role last season was incredible. He didn't play a lot of games but, despite this, his commitment is incredible and he helped me a lot in the changing room. Also to use the right work in the right moment."
Terry was recently spotted at Chelsea's training ground, a place where "the doors are always open to him," according to Conte.