The online eroakirkosta.fi service, maintained by two Finnish associations, allows people to resign from church by filling in an online form. After filling in the form, people are given an opportunity to explain their reasons for resigning in free-text format. This dataset consists of the reasons entered by 961 people when quitting the Evangelical Lutheran Church of Finland or the Finnish Orthodox Church in 2020. The dataset is part of the annually supplemented data series which examines the reasons for leaving church submitted by a sample of approximately 1,000 people on the eroakirkosta.fi online service each year. Background information includes age, gender and month of leaving church. The data were organised into an easy to use HTML version at FSD. The dataset is only available in the languages used for entering the information (mainly Finnish, a few comments in English and Swedish).