He polled 297,603 votes representing 98.9 per cent.
The Director of Electoral Services at the Electoral Commission, Dr Serebour Quiacoe announced the results in the early hours of Sunday at the NDC headquarters in Accra.
Earlier, Mr Mahama’s competitor, a former Chief Executive of the Kumasi Metropolitan Assembly, Kojo Bonsu conceded defeat and congratulated Mr Mahama for running a superior campaign.
A third contestant, Dr Kwabena Duffuor, a former Finance Minister of Finance, pulled out of the race on the eve of the elections on May 12, making it a two horse race between former President Mahama and Mr Bonsu.
In a victory speech posted on Facebook on Sunday, Mr Mahama urged all party members to remain united in winning the 2024 general elections.
He stated, “I also ask for cooperation among all our elected parliamentary candidates and the respective aspirants and supporters and all the constituencies across the country.”
He said, “our party is the winner because there are no individual winners and losers in the party’s contest.”
Mr Mahama, however, thanked his campaign team “for keeping their focus and delivering a clean campaign.”
He also expressed his gratitude to the donors and financiers of his campaign, urging them to continue to support his campaign in the 2024 elections.