Variation Margin
Variation margin represents the daily, or sometimes intraday, cash payments made between parties in a derivatives contract to account for changes in the market value of their positions. As the underlying asset price moves, the value of the contract changes, and the party losing value must pay the party gaining value to keep the contract marked-to-market.
This process ensures that losses do not accumulate over time, which reduces the total credit risk exposure between counterparties. By settling gains and losses frequently, the clearinghouse maintains a neutral risk profile for the contract.
It is a fundamental mechanism for daily risk management in futures and options trading. Without it, credit risk would build up significantly until contract maturity.