Lizaad Williams started playing cricket as a batsman and bowler and joined the South Africa Cricket Board's academy in 2015. He played for the South Africa under-15 and under-17 teams before making his first-class debut for Boland in the 2010/11 season. He made his List A debut for Boland in the same season. He was the leading wicket-taker for Boland in both formats, with 20 wickets in four matches and 17 wickets in five matches respectively. He made his Twenty20 debut for Western Province in the 2014/15 season. In November 2017, he was signed by Comilla Victorians for the 2017–18 Bangladesh Premier League season.
Lizaad Williams was named in South Africa's squad for the 2016 Under-19 Cricket World Cup. He scored an unbeaten century in the final of the 2015 ACC Under-19 Asia Cup and helped South Africa to win their maiden ACC Under-19 Cup title. In December 2018, he was named in South Africa's under-23 team for the 2018 ACC Emerging Teams Asia Cup. In November 2019, he was named in South Africa's squad for the 2019 ACC Emerging Teams Asia Cup in Bangladesh. In February 2020, he was named in South Africa's Twenty20 International (T20I) squad for their series against Pakistan. In April 2021, he made his T20I debut for South Africa, against Pakistan, on 10 April 2021. He took two wickets in that match and helped South Africa win by 11 runs. In May 2021, he was named in South Africa's Test squad for their series against Bangladesh. He made his Test debut on 31 March 2022 at Kingsmead Stadium in Durban. He took three wickets in that match but South Africa lost by an innings and 75 runs. In July 2021, he made his One Day International (ODI) debut for South Africa, against Ireland, on 16 July 2021. He took two wickets in that match but South Africa lost by 43 runs.
Lizaad Williams has played 2 ODIs for South Africa till date, scoring 0 runs at an average of 0.00. His highest score is 0 against Ireland in July 2021. He has also taken 3 wickets at an average of 39.33. His best bowling figures are 2/56 against Ireland in July 2021.
Lizaad Williams has played 9 T20Is for South Africa till date, scoring 6 runs at an average of 6.00. His highest score is 2* against Pakistan in April 2021. He has also taken 13 wickets at an average of 22.53. His best bowling figures are 3/35 against Zimbabwe in September 2020.
Lizaad Williams has played 2 Tests for South Africa till date, scoring 25 runs at an average of 8.33. His highest score is 13 against Bangladesh in April 2022. He has also taken 3 wickets at an average of 35.00. His best bowling figures are 3/54 against Bangladesh in April 2022.
Lizaad Williams has not captained South Africa in any format of the game. He has, however, led Boland and Comilla Victorians in domestic cricket.
Lizaad Williams was fined 15 percent of his match fee for showing dissent at an umpire's decision during a T20I against Zimbabwe in September 2020. He was also reprimanded for using inappropriate language during the same match. He was also involved in a heated exchange with former Indian captain Virat Kohli during an IPL match between Royal Challengers Bangalore and Joburg Super Kings on 1 May 2023. Kohli accused him of sledging his teammate AB de Villiers and confronted him after the match. The two players had to be separated by the umpires and other teammates. Lizaad later apologized for his behaviour and said that it was due to the emotions of the game.