Originally from Billings, Montana, Addison Treesh now lives in Gilette, Wyoming when she is not attending school at the University of Wyoming.
Treesh has been involved in pageantry for many years, winning her first title in 2014. She took home the Miss Wyoming's Outstanding Teen 2014 title and wowed the judges with her pointe ballet routine. She went unplaced at the Miss America's Outstanding Teen 2014 pageant, but took home $1,000 in scholarships for competing.
Treesh took home her second title when she won the International Junior Miss Wyoming Teen 2016 crown. She began to compete in the Miss Teen USA pageant system and took home a First Runner-Up placement at Miss Wyoming Teen USA 2018. In her first year in the Miss division, Treesh won Miss Wyoming USA 2019.