The former president of Ghana travelled to Bole, a venue he has been voting at since 1992.
Mahama voted around 10 am before speaking to reporters.
The former president said he expects proceedings to run smoothly on Election Day.
He, however, said one of his security details could not find his name in the register despite them checking during the exhibition period.
Talking about how he saw the process, John Mahama said:
"There was no queue. That is the usual of this polling station. I have voted here since 1992 and the process has been very simple, very smooth."
"It's too early here to make an assessment," Mahama said around his observation at the polling station.
"There are a few hitches like this polling station, there is a lady here who has got her card, her card is from this station but her name is not on the list.
"One of my security detail, I registered here with him. During the exhibition, we checked and his name was there. But we got here today and his name is not there. I don't know if it's a generalized problem but like I said it is too early here to make an assessment," he said.
Ghanaian are voting in their presidential and parliamentary elections on December 7, 2020. This is the 8th presidential and parliamentary elections in the Fourth Republic.