The service featured some of his best-known hits including "Jesus to a Child" and "Wake Me Up Before You Go Go".
It was followed by a wake at The Three Crowns pub, where Wham! were formed.
The singer was found dead at his home on December 25. He was 53.
His funeral took place in private on March 29 at Highgate Cemetery in north London and was not announced to fans until it was over.
George Michael Appreciation Group founder Tracey Wills organised Sunday's public event.
"I have always been a fan and I decided that I was going to do something for him because he has done so much for everyone else," she said.
"George left such a mark on a lot people and I felt like we needed to do something for him. The fans needed somewhere to grieve.
"I put this together for George, for the fans. I wish his family were here to be able to see this."
Michael's cause of death was dilated cardiomyopathy with myocarditis and fatty liver, according to senior coroner for Oxfordshire Darren Salter.
Dilated cardiomyopathy, which can be caused by substance abuse, affects the heart's ability to pump blood due to the muscle becoming enlarged and weakened. Myocarditis is an inflammation of the heart wall.
Born Georgios Kyriacos Panayiotou to a Greek Cypriot father and English mother in north London in 1963, Michael shot to fame with Wham! and sold more than 100 million records.
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It was followed by a wake at The Three Crowns pub, where Wham! were formed.
The singer was found dead at his home on December 25. He was 53.
His funeral took place in private on March 29 at Highgate Cemetery in north London and was not announced to fans until it was over.
George Michael Appreciation Group founder Tracey Wills organised Sunday's public event.
"I have always been a fan and I decided that I was going to do something for him because he has done so much for everyone else," she said.
"George left such a mark on a lot people and I felt like we needed to do something for him. The fans needed somewhere to grieve.
"I put this together for George, for the fans. I wish his family were here to be able to see this."
Michael's cause of death was dilated cardiomyopathy with myocarditis and fatty liver, according to senior coroner for Oxfordshire Darren Salter.
Dilated cardiomyopathy, which can be caused by substance abuse, affects the heart's ability to pump blood due to the muscle becoming enlarged and weakened. Myocarditis is an inflammation of the heart wall.
Born Georgios Kyriacos Panayiotou to a Greek Cypriot father and English mother in north London in 1963, Michael shot to fame with Wham! and sold more than 100 million records.
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