Surplus is the quantity "left over" after conducting an activity. Surplus also is the great quantity of excess and can also refer to:

• budget surplus, the opposite of a budget deficit
• economic surplus
• Surplus product or surplus value in Marxian economics
• physical surplus in the economic theory of Piero Sraffa
• Operating surplus in national accounts
• anything that's no longer considered of use, such as army surplus
• something in excess of requirements
• consumer surplus in economics
• producer surplus in economics
• capital surplus in economics
• surplus, supply and demand in economics
• surplus in Agriculture as stimulus to development of the Civilization in Socio-cultural_anthropology
• Surplus (movie) is a 2003 Swedish documentary on consumerism
• the surplus business is the buying and selling of goods for recycling, remarketing or repurposing