Sup or SUP may refer to:

• Saskatchewan United Party, a political party in Saskatchewan
• Supremum or sup, in mathematics, the least upper bound
• Societas unius personae, proposed EU type of single-person company
• SUP Media or Sup Fabrik, a Russian internet company
• Sailors' Union of the Pacific
• Scottish Unionist Party (1986), established in the mid 1980s
• Simple Update Protocol, dropped proposal to speed RSS and Atom
• Software Upgrade Protocol
• Standup paddleboarding
• Stanford University Press
• Sydney University Press
• Syracuse University Press
• Sup squark, the supersymmetric partner of the up quark
• <sup>, an HTML tag for superscript
• Supangle or sup, a Turkish dessert