Boult was a key member of the New Zealand team that won the 2019–2021 ICC World Test Championship.

[8] Trent announced his engagement to partner Gert Smith in June 2016,[9] and the couple married in August 2017 in a private ceremony at Kauri Bay Boomrock.

Following the tournament, Boult received a Maiden call-up into the Indian Premier League by the Sunrisers Hyderabad and he was purchased for $600,000.

In February 2017, he was bought by the Kolkata Knight Riders team for the 2017 Indian Premier League for 5 crores.

In June 2019, he was selected to play for the Toronto Nationals franchise team in the 2019 Global T20 Canada tournament.

On 21 January 2009, Boult was selected for the New Zealand squad for the one-day series against Australia at just 19 years of age.

Boult only managed to play in the warm up game against the Prime Minister's XI and went wicketless off seven overs.

He took four wickets in the match; additionally, he scored 21 runs in a tenth-wicket partnership with Chris Martin in the second innings.

Boult struggled in the hot and dry conditions, taking just 3 wickets and frequently straying with his accuracy.

In the second test at the Basin Reserve Boult won man of the match award, after taking career best figures of 10 for 80 and completing a brilliant one-handed diving catch to his left to dismiss Dinesh Ramdin.

In the first innings of the second test on the same venue against India, Boult made another one-handed diving right-handed catch to dismiss Ajinkya Rahane.

[38][39] In 2014, he became the 4th test bowler since Richard Hadlee, Chris Martin and Iain O'Brien to claim 30+ wickets in consecutive years.

He has developed a good opening bowling partnership with Tim Southee, having taken 46% of all wickets between them since 2013, especially since the retirement of Martin.

In August 2019, in the series against Sri Lanka, Boult became the third bowler for New Zealand to take 250 wickets in Test cricket.