	Nicholls was consecrated a bishop on February 2, 2008. She served as a Suffragan Bishop in the Anglican Diocese of Toronto, Canada from 2008 to 2016: she was in charge of the Trent Durham area of the Diocese. On February 13, 2016, she was elected coadjutor bishop of the Diocese of Huron — she was the first woman to be elected a bishop in the Diocese — and she automatically succeeded to the role of diocesan Bishop of Huron on November 1, 2016 upon the retirement of Robert Bennett.