Open market operation

Open market operations (OMOs) are a tool used by central banks to manage liquidity in the banking system. These operations involve the buying and selling of government bonds and other financial assets. The central bank can either transact government bonds in the open market or enter into repurchase agreements or secured lending transactions with commercial banks.

Central banks regularly use OMOs as one of their tools for implementing monetary policy. A frequent aim of open market operations is to influence the short-term interest rate. By buying securities, the central bank injects liquidity into the banking system, lowering interest rates. Conversely, selling securities withdraws liquidity, raising interest rates.

Since the 2008 financial crisis, the prominence of OMOs in influencing short-term interest rates has diminished for many central banks. This is because many central banks have shifted to a floor system, where there is abundant liquidity in the payments system. In this system, central banks no longer need to fine-tune the supply of reserves to meet demand.