In February 2021, after having played nine seasons for Northern Districts, and in the middle of a breakthrough season as one of the top-scoring batter in the country, Halliday earned her maiden call-up to the New Zealand squad, for their Women's One Day International (WODI) matches against England.[4][5] As part of the preparation for the series, she played in a warm-up match for the New Zealand XI Women's team, scoring 79 runs from 56 balls.[6][7] She made her WODI debut for New Zealand, against England, on 23 February 2021.[8]
On 1 March 2021, Halliday was added to New Zealand's Women's Twenty20 International (WT20I) squad, also for the matches against England.[9][10] The following day, Halliday was one of the three nominees for the Women's Player of the Month in the ICC Player of the Month Awards.[11] She made her WT20I debut for New Zealand, against England, on 3 March 2021.[12] In May 2021, Halliday was awarded with her first central contract from New Zealand Cricket ahead of the 2021–22 season.[13] In February 2022, she was named in New Zealand's team for the 2022 Women's Cricket World Cup in New Zealand.[14] In June 2022, Halliday was named in New Zealand's team for the cricket tournament at the 2022 Commonwealth Games in Birmingham, England.[15]
In September 2024, she was named in the New Zealand squad for the 2024 ICC Women's T20 World Cup.[16] Halliday scored a career-best 38 off 28 balls and took 1/4 from her single over in the final against South Africa as New Zealand won the tournament.[17][18]
Halliday was named in the New Zealand squad for their ODI tour to India in October 2024.[19]
