We have a two tiered monetary system, where one type of money is used when transacting with the Fed and between commercial banks (reserves), and another type of money is use when transacting with everyone else (bank deposits). This note explains the two types of money, and how they interact with each other.
Reserves are an unsecured liability of the Fed that can only be held by entities with an account at the Fed. Think of it as a checking account at the Fed, except that deposits in the account can only be used to pay entities who also have a checking account at the Fed. Broadly speaking, only depository institutions like commercial banks or credit unions are eligible to have accounts at the Fed. But there are also other notable entities such as the U.S. Treasury, GSEs like Fannie Mae, and clearing houses like the CME. When these entities make payments to each other, they pay in reserves.
Since reserves can only be sent to entities who also have a Fed account, the total level of reserves in the financial system cannot be changed by account holders. Reserves can never leave the Fed’s balance sheet and are simply shifted from one Fed account to another on the Fed’s balance sheet. It is a closed system. The total level of reserves is determined by Fed actions, which create or destroy reserves. Reserves are created when the Fed expands its balance sheet by buying assets, and extinguished when those assets are repaid. One exception to this is that reserves can be converted to currency at the request of commercial banks. If a commercial bank needs $1 million in currency, it calls the Fed, who then sends an armored truck carrying $1 million in currency to the commercial bank. The Fed then deducts $1 million in reserves from the commercial bank’s Fed account.Continue reading