A type of riba that exists in, or results from, a sale transaction whose underlying is a ribawi item. Riba al-buyu’ may arise either from deferment or from exchanging equal amounts. Hence, it is typically classified as:

• Riba al-nasi’ah (deferment riba): a sale transaction that involves two ribawi items exchanged on deferment. An example: the sale of 1 kg of gold at $10,000 on a deferred basis, whether one or both countervalues are deferred.
• Riba al-fadhl (surplus riba): a sale transaction that involves the exchange of one ribawi commodity (such as dates, wheat, etc) for the same type of commodity but different amount or weight. An example, the exchange of 10 kg of excellent-quality dates for 20 kg of poor quality dates.

Riba al-buyu is sometimes referred to as riba khafi/ riba khafy.