He signed a one-year deal in September, but his performances at the end of last season prompted the club to offer the 23-year-old a one-year extension.
After his impressive showings earlier in the season, Burgess was again called into first team action for Sussex’s final two Specsavers County Championship matches of the campaign as a replacement for the injured Ben Brown.
In the second of those fixtures - the draw against promoted Nottinghamshire - Burgess made his maiden first-class century. His 146 in the first innings rescued Sussex from 107-5 and helped the side to an eventual total of 565. Followers of the Sussex CCC Twitter account voted that innings as September’s Porsche performance of the month.
Making six Championship appearances in all last season, the Loughborough University graduate scored 434 runs at an average of 48.22. Alongside his hundred in the final game of the season, Burgess made fifties against Durham and Kent in May.
Explaining the decision to extend Burgess’ contract, Sussex’s director of cricket Keith Greenfield said: “It was felt by all at the club that, after further outstanding performances in the 1st XI at the end of the season, Michael deserved a further year to the one he had previously signed.
“This will give him the extra security to flourish and continue to grow with us, and we look forward to developing him further in the years to come."
Burgess added: “I’m delighted to have extended my time here at Sussex until the end of the 2019 season. It’s an exciting time to be a part of this club and I’m looking forward to what the next couple of years hold."
Burgess is one of ten Sussex players to have signed new or extended terms with the club in recent weeks.
The others are Jofra Archer, Will Beer, Tom Haines, Chris Jordan, Delray Rawlins, Abi Sakande, Phil Salt, Luke Wells and Stuart Whittingham.