[10] Ahead of the 2017 season, Ackermann signed for English county side Leicestershire on a two-year contract.
[17] In July 2022, in the County Championship, Ackermann scored his maiden double century in first-class cricket with 277 not out.
[18] In June 2019, Ackermann became available to play for the Netherlands cricket team, ahead of the 2019 ICC T20 World Cup Qualifier tournament in the United Arab Emirates.
[19] In September 2019, he was named in the Dutch squads for the 2019–20 Oman Pentangular Series and the 2019 ICC T20 World Cup Qualifier tournament.
[22] In November 2021, Ackermann was named in the Dutch One Day International (ODI) squad for their series against South Africa.