[2] In January 2013 he was called up to the England Under-19 following an injury to captain Shiv Thakor,[3] playing four Youth One Day Internationals against South Africa Under-19s during the tour.

[5] In that same month he was required as a substitute wicket-keeper for Hampshire in their Yorkshire Bank 40 match against Lancashire following an injury during the warm-up to Adam Wheater.

At the end of the 2016 season, Alsop was selected for the upcoming England Lions tour to the UAE and Sri Lanka in the new year.

In March 2022, Alsop was loaned to Sussex for the 2022 season[9] and later signed a permanent contract with the team in early June.

[10] Alsop played for the Brisbane Heat as an overseas draft pick in the Australian Twenty20 Big Bash League during the 2024-25 season.