The 26-year-old, who joined the club from Orbit College in Rustenburg in the 2014/15 season, would have seen his previous deal expire at the end of this month.
He scored four goals in 31 matches in all competitions this past season as the Team of Choice finished an unprecedented fourth in the league and reached their first Nedbank Cup final, where they came up short against Free State Stars.
Pogiso Sanoka has likewise just penned a three-year extension, having also joined United from Orbit College.
"Mokate has also been given a three-year deal by the club," Maritzburg chairman Farook Kadodia confirms to KickOff.com.
Meanwhile, the Team of Choice are believed to have transfer-listed Cameroon attacking midfielder Yazid Atouba, who only linked up with the side in August.
The former AS Vita man featured in 15 games under coach Fadlu Davids.
Maritzburg have also tied down the services of Belgian striker Andrea Fileccia and signed defender Denwin Farmer from SuperSport United, while they are thought to be interested in Matsatsantsa attacker Fagrie Lakay, as well as Mamelodi Sundowns forward Bongi Ntuli.