The winger has signed a four-year-deal at the Luzhniki Stadium in a move believed to be worth Ã‚Â£9.5 million.
Valery Karpin, the Spartak manager, is a long-term admirer of the McGeady. The recruitment of the excitingÃ¢â‚¬â€and at times unpredictableÃ¢â‚¬â€attacking midfielder will prove a major coup for the nine-time Russian champions.
McGeady made 252 appearances and scored 37 goals for The Hoops during six-year spell at Parkhead.
“I would like to take this opportunity to thank everyone at Celtic Football Club for making my time here so enjoyable and memorable,” the 24-year-old told Celtic’s website.
“The Celtic fans are second to none and it is a fantastic club to play for. Celtic is the team I have supported my whole life and will miss so many things, however I am looking forward to the challenge of playing for Spartak Moscow.”
Russian international and former Celtic goalkeeping coach Dmitri Kharine recently stated his belief that Karpin will opt to build his Spartak side around McGeady’s strengths.
“Karpin appreciates McGeadyÃ¢â‚¬â„¢s talents and will believe in him,” he said. “I expect him to build the Spartak team around McGeady and give him responsibility to be the main creative player.”
Kharine continued: “He will encourage McGeady to express himself on the pitch. If Aiden tries something unpredictable in an attack and it doesnÃ¢â‚¬â„¢t work, Karpin will not criticise him. He will applaud his creativity. He does not believe in punishing players when they try to entertain.
“They have shown their belief in McGeady by paying so much money.”
Spartak Moscow have recently experienced a domestic drought with their last league title arriving in 2001.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news