There are six churches within the City of Groton
- Christian Missionary Alliance Church, served by Pastor Bill Duncan, has worship at 10:45 a.m. every Sunday with Sunday School at 9:15 a.m. A midweek family hour is held every Wednesday at 7 p.m.
- First Presbyterian Church, served by Pastor Terry Kenny, has adult Bible study and Sunday School at 9:30 a.m. followed by worship services at 11 a.m. every Sunday.
- Emmanuel Lutheran Church (ELCA), served by Pastor Elizabeth Johnson, has worship every Sunday at 9 a.m. followed by Sunday School at 10:15 a.m. See their website for complete information on other activities.
- St. Elizabeth Ann Seton Catholic Church, served by Father Michael Kelly, holds mass on Saturday nights at 4:30 p.m. and on Sundays at 9 a.m.
- St. John’s Lutheran Church (LCMS), served by Pastor Craig Grams, has worship every Sunday at 9 a.m. followed by Sunday School and adult Bible study at 10 a.m. Confirmation and adult Bible studies are on Wednesday afternoons and evenings.
- United Methodist Church, served by Pastor Matt Richards, has worship at 11 a.m. every Sunday. For a complete list of their activities, see their website.