In 2019, Starc maintained his dominance at the international level by breaking records in the Australian domestic one-day tournament, which came about due to postponement of Australia's tour of Bangladesh. The pure numbers from Starc's tournament underlined his dominance: 26 wickets from six matches at an average of 8.12 and a strike rate of 12.3. Starc was named as Player of the Tournament in the tournament in which New South Wales won.
In April 2019, he was named in Australia's squad for the 2019 Cricket World Cup. In Australia's match against the West Indies, Starc became the quickest bowler, in terms of number of matches, to take 150 wickets in ODIs, doing so in his 77th game, thus achieving this feat one match quicker than Saqlain Mushtaq, who did it in 78 games. Australia went on to win the match by 15 runs with Starc finishing on 5/44 in his 10 overs. On 29 June 2019, in the match against New Zealand, Starc became the first bowler to take three five-wicket hauls at the Cricket World Cup. He finished the tournament with 27 dismissals, which is an all time record for most wickets as an individual in a single World Cup.
In July 2019, he was named in Australia's squad for the 2019 Ashes series in England. Although, he just played a solitary game in the Ashes, taking 4 wickets across two innings, as Australia chose to rotate their fast bowlers over the course of the series. On 16 July 2020, Starc was named in a 26-man preliminary squad of players to begin training ahead of a possible tour to England following the COVID-19 pandemic. On 14 August 2020, Cricket Australia confirmed that the fixtures would be taking place, with Starc included in the touring party.