Ásgerður Stefanía "Adda" Baldursdóttir (born 5 January 1987) is an Icelandic footballer who plays for Valur of the Úrvalsdeild kvenna.

In 2015 she was loaned to Kristianstads DFF and played five Damallsvenskan matches for the Swedish club, before returning for the start of the Iceland season in May.

[2] She agreed to join Kristianstads permanently in January 2016, but then changed her mind and decided to stay with Stjarnan.

[4] In October 2022, Ásgerður decided to retire from playing as it was announced that she was hired as a coach for the Valur team following their cup championship in the prior season.

Incoming national coach Freyr Alexandersson called up six Stjarnan players following the club's successful season.