Saint Thomas or St. Thomas may refer to:

• Thomas the Apostle (died AD 72), syrian-Christian Apostle, church of the east syric rite founder, and Saint of the 1st century
• Thomas the Hermit, Coptic Desert Father and Saint of the 4th century
• Thomas of Maurienne or Thomas of Farfa Abbey (died 720), the first abbot of the Abbey of Farfa
• Thomas Becket (died 1170), also called Saint Thomas of Canterbury and Saint Thomas the Martyr
• Thomas Aquinas (1225–1274), Catholic philosopher and theologian
• Thomas Cantilupe, or Thomas of Hereford (died 1282)
• Thomas of Dover or Thomas Hales (died 1295), martyr
• Thomas of Tolentino (died 1321), martyred in India
• Thomas, 2nd Earl of Lancaster (1278–1322), venerated as a saint after his execution
• Thomas of Villanova (1488–1555), Spanish friar of the Order of Saint Augustine, writer, archbishop
• Thomas More (1478–1535), English lawyer, philosopher, author, statesman
• Thomas Percy, 7th Earl of Northumberland, (1528-1572) Earl of Northumberland, leader of the Rising of the North, Martyr
• Thomas Danki (died 1597), see Saints Paul Miki and Companions
• Thomas Kozaki (died 1597), see Saints Paul Miki and Companions
• Thomas Garnet (died 1608), Jesuit priest who was executed in London
• Thomas De Van Nguyen (died 1839), of the Vietnamese Martyrs
• Thomas Du Viet Dinh (died 1839), of the Vietnamese Martyrs
• Thomas Thien Tran (died 1838), of the Vietnamese Martyrs
• Thomas Toan, of the Vietnamese Martyrs
• Thomas Khuong, of the Vietnamese Martyrs
• Saint Thomas (basketball), (born 2003) American college basketball player

• São Tomé, Rio Grande do Norte, municipality in Rio Grande do Norte, Brazil
• Sâo Tomé, Paraná, city in Paraná, Brazil

• St. Thomas, Newfoundland and Labrador, Canada
• St. Thomas, Ontario, Canada
• Saint-Thomas, Quebec, Canada
• Saint-Thomas-Didyme, Quebec, Canada
• Saint-Thomas-d'Aquin, former municipality now part of Saint-Hyacinthe, Quebec, Canada
• Saint-Thomas-de-Pierreville, former municipality now part of Pierreville, Quebec, Canada

• Saint-Thomas, Aisne, France
• Saint-Thomas, Haute-Garonne, France

• St Thomas, Exeter, United Kingdom
• St Thomas, Swansea, United Kingdom
• St. Thomas (electoral ward), Swansea, Wales
• St Thomas the Apostle Rural, a civil parish in Cornwall, United Kingdom

• Saint Thomas, Indiana, an unincorporated community
• St. Thomas, Minnesota
• St. Thomas, Missouri
• St. Thomas, Nevada, a sunken town
• St. Thomas, North Dakota
• St. Thomas Township, Pennsylvania
• Saint Thomas, U.S. Virgin Islands, an island in the Caribbean Sea
  • Saint Thomas (Brandenburg colony), a former settlement on this island

• Saint Thomas, Barbados
• Saint Thomas Parish, Jamaica, once known as Saint Thomas in the East
• Saint Thomas, U.S. Virgin Islands

• St Thomas de Guyana, or St Thomas of Oronoque, is today Ciudad Bolívar on the Orinoco River

• St. Thomas Island, Bulgaria
• St. Thomas Mount, a hillock in Chennai, India where, according to tradition, the biblical Thomas the Apostle was killed
• St. Thomas (County Dublin), a civil parish incorporating Jobstown, Ireland
• San Tomás (St. Thomas), former name of San Benedicto Island, Mexico
• São Tomé (St. Thomas), an island in São Tomé and Príncipe
• Saint Thomas's Gate, also known as Bab Tuma, a district of Damascus, Syria

• St. Thomas College, Kozhencherry, Kozhencherry, Kerala, India
• St Thomas College of Engineering and Technology, Kannur, Kerala, India
• St. Thomas College, Palai, Kerala, India
• St. Thomas College, Thrissur, Kerala, India
• St. Thomas' College, Dehradun, secondary school in Dehradun, Uttarakhand, India
• St. Thomas Higher Secondary School, Kozhencherry, Kerala, India

• S. Thomas' College, Bandarawela, a private school
• S. Thomas' College, Gurutalawa, a private Christian school
• St. Thomas' College, Kotte, a Catholic school
• St. Thomas' College, Matale, a secondary school
• St. Thomas' College, Matara, a government school for boys
• S. Thomas' College, Mount Lavinia, a private Anglican school
• S. Thomas' Preparatory School, Kollupitiya, a private Anglican school

• Saint Thomas Academy, a high school in Minnesota
• Saint Thomas Choir School, New York, New York
• St. Thomas University (Florida), Miami, Florida
• St. Thomas University School of Law, Miami, Florida
• St. Thomas' Episcopal School, Houston, TX
• University of Scranton, Scranton, Pennsylvania, founded in 1888 as St. Thomas College, renamed in 1938
• University of St. Thomas (Minnesota), St. Paul, Minnesota
• University of St. Thomas (Texas) Houston, Texas
• St. Thomas-St. John School District, US Virgin Islands

• "St. Thomas" (song), a jazz composition by saxophonist Sonny Rollins
• St. Thomas: Tribute to Great Tenors, a 1991 album by the New York Unit
• Thomas Hansen (musician) (1976–2007), Norwegian musician who performed under the name Saint Thomas
• A hymn composed by Aaron Williams

• Saint Thomas Christians, an ancient community of Christians from Kerala, India
• St Thomas' Hospital, Southwark
• St. Thomas University (New Brunswick), Fredericton, New Brunswick, Canada
• Thomasleeha or St. Thomas, a 1975 Malayalam historical film about Thomas the Apostle in India

• Santo Tomas (disambiguation)
• St. Thomas' Church (disambiguation)
• St. Thomas Hospital (disambiguation)
• St. Thomas station (disambiguation)