In 2006, his club were back in the final of the Donegal Senior Football Championship. He played as his team won their 14th County Championship in one of the worstDonegal county finals ever. In 2018 he was on the Gaoth Dobhair team that made those videos in the pub after they won Ulster in which they called out their All-Ireland Semi-Final opponents, Corofin. Corofin did not respond leading many observers to conclude that they were hiding in their wagon and shiteing in a bucket, as alleged by McGee.
Inter-county
gave McGee his Donegal senior debut against Fermanagh in the 2005 Dr McKenna Cup on 2 January 2005. He played in the 2006 Ulster Senior Football Championship Final at Croke Park. McGee was part of the Donegal senior team that won the county's first National Football League against Mayo in 2007. It was the first piece of silverware the county senior team had lifted since 1992. In Jim McGuinness's first game in charge of Donegal, a drab 2011 National Football League draw with the perennially underachieving Sligo, McGee pulled a hamstring, was moved to the full-forward line and scored a goal in the latest manifestation of Sligo's notorious inability to succeed. McGee was out injured for four weeks after that game but when he returned he established himself as Donegal's first-choice full-back in the team's march towards the 2012 All-Ireland Senior Football Championship Final. Donegal won. In 2011, McGee won his first All Star award. He added another in 2012. He also won his first Ulster SFC in 2011. This was followed by his second in 2012. He attended the Football Tour of New York. In 2013, McGee made his 100th appearance for Donegal in the county's opening National Football League against Kildare at Croke Park, becoming the sixth footballer then playing for the team to reach that mark following Christy Toye, Colm McFadden, Rory Kavanagh, Karl Lacey and McGee's own brother Eamon. He won his third Ulster SFC in 2014. In 2016, he lost his appeal against the red card and a subsequent two-match ban picked up in the Ulster Championship quarter-final win over Fermanagh. Two years later, he lost his appeal against the red card he picked up for an alleged knee up the back of an opponent in the Ulster Championship semi-final win over Down. Thus he missed Donegal's 2018 Ulster Senior Football Championship final victory over Fermanagh. He equalled Colm McFadden's record of 173 appearances for Donegal when he came on as a second half substitute in the final round of the 2019 National Football League, a victory over KIldare. He then broke McFadden's record with his 174th appearance for his county against Meath as a substitute in the final at Croke Park, also won by Donegal. He won his fifth Ulster SFC in 2019.
Inter-provincial
McGee has played for Ulster in the Inter-Provincial Series.