Not true. There is only one Fed regulation about how much central bank money a bank must have, and that is the minimum reserve requirement, which is currently 1

Not true. There is only one Fed regulation about how much central bank money a bank must have, and that is the minimum reserve requirement, which is currently 10% for sufficiently large banks. This is a required ratio between accounts of clients of the bank and money that the bank itself has in its account at the Fed (or as cash in its vaults). As such, it does not even have anything to do with loans in the first place. The only way it has anything to do with loans is that as a loan of e.g. $1000 million is created, the bank creates a new account or marks up an existing account to the extent of $1000 million. The minimum reserve requirement then increases by 10% of the newly created money, i.e. by $100 million. If the bank does not already have a sufficient amount of central bank money in its accounts, it must obtain this money within the next two weeks or so. This is what happens in practice: Banks create loans based on creditworthiness of potential borrowers. An institutionally separate department of the bank then ensures sufficient central bank money to satisfy regulations. tl;dr: Your number of $1.1 billion is completely wrong. The number $100 million would be somewhat less wrong, but is still not correct. In reality, banks do not need any money to make loans. They do need to satisfy minimum reserve requirements, but if necessary, they can obtain the required money after the loan is made.