Thomas Onslow

Thomas Onslow may refer to:


 * Thomas Onslow, 2nd Baron Onslow (1679–1740), British politician and landowner
 * Thomas Onslow, 2nd Earl of Onslow (1754–1827), English nobleman and courtier
 * Thomas Cranley Onslow (1778–1861), British politician and soldier
 * Thomas Frederick Onslow (1821–1883), English cricketer