Clay is both an English surname, a masculine given name, often short for Clayton, and a nickname.

As of 2014, 76.1% of all known bearers of the surname Clay were residents of the United States (frequency 1:5,846), 12.5% of England (1:5,460), 2.7% of Australia (1:10,816), 1.4% of Canada (1:31,264) and 1.2% of France (1:69,714).

In England, the frequency of the surname was higher than average (1:5,460) in the following counties:

• 1. Nottinghamshire (1:1,287)
• 2. Derbyshire (1:2,238)
• 3. Lincolnshire (1:2,318)
• 4. Staffordshire (1:2,357)
• 5. Leicestershire (1:2,705)
• 6. Warwickshire (1:2,752)
• 7. West Yorkshire (1:2,838)
• 8. Herefordshire (1:2,856)
• 9. South Yorkshire (1:3,014)
• 10. Shropshire (1:3,271)
• 11. North Yorkshire (1:4,378)
• 12. Cornwall (1:4,867)
• 13. Hertfordshire (1:5,093)
• 14. Cambridgeshire (1:5,301)

In the United States, the frequency of the surname was higher than average (1:5,846) in the following states:^[1]

• 1. West Virginia (1:1,501)
• 2. Mississippi (1:1,690)
• 3. Georgia (1:2,391)
• 4. Arkansas (1:2,794)
• 5. Alabama (1:2,876)
• 6. Missouri (1:3,086)
• 7. Kentucky (1:3,223)
• 8. Louisiana (1:3,418)
• 9. Oklahoma (1:3,507)
• 10. Tennessee (1:3,769)
• 11. Ohio (1:4,169)
• 12. Virginia (1:4,296)
• 13. Texas (1:4,473)
• 14. North Carolina (1:4,705)
• 15. Illinois (1:5,138)
• 16. Michigan (1:5,431)
• 17. Maryland (1:5,696)
• 18. Indiana (1:5,723)

• Adam Clay (disambiguation), several people
• Alfred Borron Clay (1831–1868), British artist
• Allyson Clay, Canadian artist
• Bryan Clay (born 1980), American gold medalist in the decathlon at the 2008 Summer Olympics in Beijing
• Muhammad Ali (born Cassius Clay, 1942–2016), American boxer
• Cassius Marcellus Clay (politician) (1810–1903), American politician, abolitionist
• Cassius Marcellus Clay Sr. (1912–1990), American painter and musician and father of Cassius Clay (Muhammad Ali)
• Charles Clay (disambiguation), several people
• Craig Clay (born 1992), English footballer
• Edward Clay (born 1945), British diplomat
• Edward Sneyd Clay (c. 1768 – 1846), British naval officer
• Eric Clay (1922–2007), British rugby league referee
• Ethel Clay (1874–1943), American nurse and socialite
• Frederic Clay (1838–1889), British composer
• Frederick William Clay (1927–1983), known as Freddie, Indigenous Australian activist on Palm Island, Queensland (husband of Iris)
• Grady Clay (1916–2013), American journalist
• Henry Clay (disambiguation), multiple people
  • Henry Clay (1777–1852), American statesman and orator
• Iris Clay (1936–1979), Indigenous Australian activist on Palm Island, Queensland (wife of Fred)
• James Clay (disambiguation), several people
• John Clay (disambiguation), several people
• Kaelin Clay (born 1992), American football player
• Lacy Clay (born 1956), U.S. House Representative
• Lauren Clay (born 1982), American artist
• Lucius D. Clay (1897–1978), American general and military governor
• Otis Clay (1942–2016), American R&B and soul singer
• Philippe Clay (1927–2007), French singer
• Raven Clay (born 1990), American hurdler
• Rosa Clay (1875–1959), a Namibian-born Finnish American teacher, singer and choral conductor
• Rudy Clay (politician) (1936–2013), American politician
• Rudolph Valentino Clay (born 1943), rechristened from Rudolph Arnett at birth, given name of American boxer Rahaman Ali, brother of Cassius Clay (Muhammad Ali)
• Sam Clay (born 1993), American baseball player

• Clay Aiken (born 1978), American popular music singer
• Clay Buchholz (born 1984), Major League Baseball pitcher for the Boston Red Sox
• Clay Calvert American lawyer and academic
• Clay Martin Croker (1962–2016), American voice actor and animator
• Clay Dalrymple (born 1936), former American professional baseball player
• Clay Dreslough, American video game designer
• Clay Guida (born 1981), American mixed martial artist
• Clay Hensley (born 1979), American baseball player
• Clay Higgins (born 1961), American politician
• Clay Jenkins (born 1964), American politician and lawyer
• Clay S. Jenkinson (born 1955), American Rhodes Scholar and popular historical re-enactor
• Clay Johnston (academic), American neurologist and university administrator
• Clay Johnston (American football) (born 1996), American football player
• Clay Kaytis (born 1973), American animator and director
• Clay Matthews Sr. (1928–2017), American football player
• Clay Matthews Jr. (born 1956), American football player, son of the above
• Clay Matthews III (born 1986), American football player, son of the above
• Clay Riley, American politician
• Clay Milner Russell (born 1999), English actor
• Clay V. Spear (c. 1914 – 1974), associate justice of the Idaho Supreme Court
• Clay Sweeting, Bahamian politician
• Clay Travis (born 1979), American sports journalist
• Clay Walker (born 1969), American country music singer
• Clay Webb, American football player
• Clay (born 1999), pseudonym Dream, American YouTuber and Minecraft gamer

• Clay Cook (born 1978), American guitarist, keyboardist, mandolinist, steel guitarist, and vocalist in Zac Brown Band
• Clay Regazzoni (1939–2006), Swiss racing car driver

• Clay, the first host of Playhouse Disney
• Clay (Pokémon), in the Pokémon universe
• Clay Bailey, in the American animated television series Xiaolin Showdown
• Clay Calloway, from the film Sing 2
• Clay Davis, in American TV series The Wire
• Clay Jensen, in the novel and Netflix series 13 Reasons Why
• Clay Kaczmarek, from the Assassin's Creed games
• Clay Moorington, a character in Nexo Knights
• Clay Morrow, from American TV series Sons of Anarchy
• Clay Puppington, the main antagonist of the American TV series Moral Orel
• Clay Simons, in the game Grand Theft Auto: The Lost and Damned
• Clay Terran, from the game series Ace Attorney: Dual Destinies
• Caduceus Clay, from the American web series Critical Role
• Faceas Clay, an antagonist from the Strider Hiryu manga and NES game
• Clay, a villager from the Nintendo Switch game “Animal Crossing”

• Claye