TRADING GLOSSARY
Open interest
Open interest is the number of outstanding derivatives contracts, such as futures or options, that have not been closed or expired. Each contract is counted once despite having both a buyer and a seller, unlike volume, which measures trading activity.
EXAMPLE
In a hypothetical futures market, open interest is 100 contracts. If a new buyer and new seller create 10 additional contracts, open interest rises to 110.
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Risk warning: CFDs are complex instruments and come with a high risk of losing money rapidly due to leverage. You should consider whether you understand how CFDs work and whether you can afford to take the high risk of losing your money. Glossary definitions are general education only and are not investment advice. Risk disclosure