• Consumer surplus occurs when the price consumers pay for a product or service is less than the price they are willing to pay.

  • Consumer surplus is based on the economic theory of marginal utility, which is the additional satisfaction a consumer receives from one more unit of a good or service. Consumer surplus always increases when the price of a good falls and decreases when the price of a good rises.
  • Economists visualize it as a triangular area under the demand curve between the market price and what consumers would be willing to pay.
  • Consumer surplus plus producer surplus equals total economic surplus.