Tam is a short form of Thomas in Scots, a nickname and a surname. It may refer to:
- Tamunoemi "Tam" David-West (1936–2019), Nigerian academic, social critic and former federal minister
- Tam Joseph (born 1947), Dominica-born British painter formerly known as Tom Joseph
- Tam or Tom Kellichan (born c. 1954), Scottish musician, The Skids original drummer (1977–1979)
- Tam Lenfestey (1818–1885), Guernsey poet
- Tamandani "Tam" Nsaliwa (born 1982), Malawian footballer
- Walter Sumner "Tam" Rose (1888–1961), American football player and head coach
- Hubert Tamblyn "Tam" Spiva (1932–2017), American television screenwriter of The Brady Bunck and Gentle Ben
- the Cantonese romanisation of Tan (surname) (譚), a common Chinese surname
- Reuben Tam (1916–1991), American artist
- Rabbeinu Tam (1100–1171), Rabbi Jacob Tam
- Rod Tam (1953–2019), American businessman and politician
- John Tams (born 1949), English actor, singer, songwriter, composer and musician