Terry had surgery in France last week to cure a back problem and has been sidelined since a league win over Newcastle United on Dec. 13.
Speaking before Tuesday's league game at Aston Villa, Mourinho told Sky Sports: "This will be the last Premiership game Terry will miss.
"I think Terry will be back for the next (Premiership) game against Wigan."
Chelsea have suffered at the back since losing their England central defender, conceding two goals in each of their last four league games, with two wins and two draws.
Mourinho also said that Dutch winger Arjen Robben, absent since scoring a late winner at Wigan on Dec. 23, could return for the home Wigan game.