The interbank lending market is a market in which banks extend loans to one another for a specified term. Most interbank loans are for maturities of one week or less, the majority being overnight. Such loans are made at the interbank rate (also called the overnight rate if the term of the loan is overnight). A sharp decline in transaction volume in this market was a major contributing factor to the collapse of several financial institutions during the financial crisis of 2007.
Banks are required to hold an adequate amount of liquid assets, such as cash, to manage any potential bank runs by clients. If a bank cannot meet these liquidity requirements, it will need to borrow money in the interbank market to cover the shortfall. Some banks, on the other hand, have excess liquid assets above and beyond the liquidity requirements. These banks will lend money in the interbank market, receiving interest on the assets. Interbank lending market