Therefore, all Twenty20 matches played between Guernsey women and another international side after 1 July 2018 were eligible for full WT20I status.

[6] Guernsey played their first WT20I on 31 May 2019, defeating neighbours Jersey by seven wickets in the 2019 T20 Inter-Insular Cup at College Field, Saint Peter Port.

During the match opening batter Philippa Stahelin scored the first WT20I half-century by a Guernsey player with 56 not out from 52 balls.

[7][8][9] On 5 May 2024, Hannah Mechem[n 1] became the first Guernsey bowler to take a five-wicket haul in a WT20I when she bagged 6/6 against the Isle of Man in the second game of a three-match bilateral series held at the Norman Edwards Memorial Ground, Winchester, England.

[10][11][12] In August 2024, Guernsey won three out of four matches to finish as runners-up in the 2024 Women's Nordic Cup with victories over Estonia, hosts Norway and a Finland XI while their solitary defeat came in their opening contest against eventual tournament champions Denmark by just five runs.