Earlier this month, several media outlets revealed the Real Madrid coach has agreed a deal to return to Stamford Bridge at the end of the season, where he twice lifted the Premier League title.
Terry has now revealed he and Frank Lampard are among those who still speak with the 50-year-old, often exchanging messages of good luck prior to their respective matches.
"Mourinho has a great relationship with our fans because we won the Premier League and several other titles with him," Terry told Marca. "Real Madrid must be respected, as he is under contract. The fans have clearly shown that he is the man they want after everything he won. He's still 'The Special One'.
"We send each other text messages and often wish each other good luck. He's interested in our results and everything that happens at the club. He's not only in contact with me but also with [Frank] Lampard and other players.
"He's been winning titles at Real for three years and he has the chance to win the Copa del Rey this season. All I can say is that he's a top manager who I really enjoyed working under...We worked hard and we could also talk to him about personal problems. He was a friend. We were all sad when he left."