In Great Britain the money market consists of a number of linked markets, all of them concentrated in London. The 12 specialist banks known as discount houses have the longest history as money market institutions; they have their origin in the London bill broker who in the early 19th century made the market in inland commercial bills. By selling bills through this market, the growing industrial and urban areas were able to draw upon the surplus savings of the agricultural areas. Quite early many bill brokers began to borrow money from banks in order to buy and hold these bills, instead of simply acting as brokers, and thus became the first discount houses. Since then the major assets held by the discount houses have at different times been commercial bills (first inland bills as described above and later bills financing international trade), treasury bills, and short-dated government bonds. During the 1960s there was a resurgence of the commercial bill, which finally became the discount houses’ largest single class of asset, only to be overtaken later by the certificate of deposit.

Important changes were introduced into the British monetary system in 1971, but money at call with the discount houses retained its role as a reserve asset. Such is the safety and liquidity of call money that, despite the fractionally lower rate on it compared with other reserve assets, the banks hold about half of their required reserves in this form. This in turn provides the discount houses with a large pool of funds, which they invest in relatively short-dated assets, of which the most important is sterling certificates of deposit, followed by commercial bills, local authority securities, and treasury bills. This pattern of assets is greatly influenced by the fact that all call loans to the discount houses are secured loans, parcels of assets being deposited pro rata with the lending banks as security, and the assets held by the discount houses must therefore be suitable for use as such security.

They also need to hold a substantial proportion of assets that are rediscountable at the Bank of England in case of need, and the Bank of England limits their holding of assets other than public sector debt to a maximum of 20 times their capital resources.

On the liabilities side of the discount house’s balance sheet, operating in call money is part of its day-to-day work. A bank that expects to make net payments to other banks during the day (for example, in settlement of checks paid by its customers to their customers) will probably call in some of its call loans, and by convention this is done before noon. Since the banks that have called in money then pay it to other banks, these other banks will have an equal amount to re-lend to the discount houses in the afternoon. Thus the discount houses can “balance their books”—borrow enough money in the afternoon to replace the loans called from them in the morning.

It is not uncommon for perhaps £100,000,000 to be called from, and re-lent to, the discount houses on an active day.

There is one main reason why the money position may not balance in this way. The British government accounts are kept with the Bank of England, which does not lend at call as other banks do. Thus net payments into or out of these government accounts will cause a net shortage or surplus of money for the discount houses in the afternoon and will tend to cause money rates to rise or fall. The Bank of England can allow such shortages or surpluses to affect interest rates, or it can offset them by buying or selling bills or by lending overnight to the discount houses at market rates. Even if the Bank of England does not act in this way to meet a shortage of funds, the discount houses are always finally able to secure the funds they need by their right to borrow from the Bank of England (the lender of last resort) against approved security at the “minimum lending rate” (the penalty rate).

On the assets side of their balance sheets, the discount houses are active dealers in a number of the assets they hold. They make the market in sterling certificates of deposit and in commercial bills, quoting buying and selling rates for different maturities. They also quote selling rates for treasury bills that they acquire at the weekly tender in competition with each other and with any other banks that may tender, including the Bank of England. Most of these other banks tender for treasury bills in order to hold them to maturity, but the discount houses sell theirs on the average when only a few weeks of the bills’ 91-day life has passed. A large proportion of these bills is sold to the clearing banks, which do not tender on their own account.

The Bank of England minimum lending rate is normally determined for each week 0.5–0.75 percent above the average treasury bill rate at the previous Friday’s tender. The bank, however, has the power to fix it at a different level if it so wishes, and this has been done.

Important changes have also occurred outside the discount market described above; after the mid-1950s there was steady growth in public borrowing by local authorities. This led to an active local authority loan market conducted through a number of brokers, where money can be lent on deposit for a range of maturities from two days up to a year (and indeed for longer periods). Much more rapid was the growth after the mid-1960s of the interbank market, in which banks borrow and lend unsecured for a range of maturities from overnight upward. This market also is conducted through brokers, often firms that also operate in the local authority and other markets; a number of these firms of brokers are subsidiaries of discount houses.

In addition to the markets mentioned, there is the gilt-edged (government bond) market on the stock exchange; short-dated bonds are held by the discount houses and by banks and other money market participants, as are short-dated local authority stocks and local authority “yearling” (very short-dated) bonds. With flexibility of bank deposit rates (at least for deposits of large denomination), both banks and nonbank transactors are faced with a wide and competitive range of sterling money market facilities in London.

Finally, mention should be made of the Eurodollar market, because London is its centre; this is an entrepôt market with a very large volume of business in U.S. dollar balances, conducted through brokers (often the same firms that operate in the sterling markets), and U.K. banks are active participants. However, owing to exchange control there has been little significant interaction between the Eurodollar market and the U.K. domestic money market.