On 1 June 2014, she appeared as a substitute in the FA Girls' Youth Cup final against Liverpool held at Stadium MK.

[5] On 1 November 2020, MacIver won the player of the match award in the 2020 Women's FA Cup Final, despite Everton losing 1–3 after extra time to her former club Manchester City.

[7] She made only three league appearances in her first season, with Ellie Roebuck the regular starter, and none in her second campaign as Khiara Keating became the preferred first choice; MacIver then suffered a serious knee injury in April 2024 while on international duty.

[11] MacIver was part of the England squad that won bronze medal in the 2018 U20 World Cup in France, and was awarded the Golden Glove as the tournament's best goalkeeper.

[18][19] MacIver was allotted 218 when the FA announced their legacy numbers scheme to honour the 50th anniversary of England’s inaugural international.

[23] Despite Bardsley being forced to withdraw a month prior to the tournament, MacIver remained a reserve player and Hege Riise called-up the previously unnamed Carly Telford as a replacement instead.

[30] On 5 April 2024, MacIver suffered an anterior cruciate ligament injury during a UEFA Euro 2025 qualification match against Serbia.