Paying a glowing tribute to his former boss John Evans Atta Mills, Mahama said he was building "a better Ghana" for all and not just a few in the country.
In a Facebook post, Mahama said Mills' sterling leadership qualities will never be forgotten.
He said Professor Mills was a humane leader who strove to ensure better socio-economic conditions for Ghanaians adding that his footprints are all over the country.
Mahama further stressed that the late Atta Mills was a true leader, a visionary, and a friend to many.
Prof Mills passed on July 24, 2012, becoming the first sitting President in Ghana’s Fourth Republic to die.
Then serving as Prof. Mills' Vice President, Mahama was subsequently sworn in to replace his deceased boss as President.