Currency prices are constantly moving, so the trader may decide to hold the position overnight. The broker will rollover the position, resulting in a credit or debit based on the interest rate differential between the Eurozone and the U.S. If the Eurozone has an interest rate of 4% and the U.S. has an interest rate of 3%, the trader owns the higher interest rate currency because they bought EUR. Therefore, at rollover, the trader should receive a small credit. If the EUR interest rate was lower than the USD rate then the trader would be debited at rollover.
The modern foreign exchange market began forming during the 1970s. This followed three decades of government restrictions on foreign exchange transactions under the Bretton Woods system of monetary management, which set out the rules for commercial and financial relations among the world's major industrial states after World War II. Countries gradually switched to floating exchange rates from the previous exchange rate regime, which remained fixed per the Bretton Woods system.
Foreign exchange is traded in an over-the-counter market where brokers/dealers negotiate directly with one another, so there is no central exchange or clearing house. The biggest geographic trading center is the United Kingdom, primarily London. In April 2019, trading in the United Kingdom accounted for 43.1% of the total, making it by far the most important center for foreign exchange trading in the world. Owing to London's dominance in the market, a particular currency's quoted price is usually the London market price. For instance, when the International Monetary Fund calculates the value of its special drawing rights every day, they use the London market prices at noon that day. Trading in the United States accounted for 16.5%, Singapore and Hong Kong account for 7.6% and Japan accounted for 4.5%.
At the end of 1913, nearly half of the world's foreign exchange was conducted using the pound sterling. The number of foreign banks operating within the boundaries of London increased from 3 in 1860, to 71 in 1913. In 1902, there were just two London foreign exchange brokers. At the start of the 20th century, trades in currencies was most active in Paris, New York City and Berlin; Britain remained largely uninvolved until 1914. Between 1919 and 1922, the number of foreign exchange brokers in London increased to 17; and in 1924, there were 40 firms operating for the purposes of exchange.
Money transfer companies/remittance companies perform high-volume low-value transfers generally by economic migrants back to their home country. In 2007, the Aite Group estimated that there were $369 billion of remittances (an increase of 8% on the previous year). The four largest foreign markets (India, China, Mexico, and the Philippines) receive $95 billion. The largest and best-known provider is Western Union with 345,000 agents globally, followed by UAE Exchange. Bureaux de change or currency transfer companies provide low-value foreign exchange services for travelers. These are typically located at airports and stations or at tourist locations and allow physical notes to be exchanged from one currency to another. They access foreign exchange markets via banks or non-bank foreign exchange companies.
Both types of contracts are binding and are typically settled for cash at the exchange in question upon expiry, although contracts can also be bought and sold before they expire. The forwards and futures markets can offer protection against risk when trading currencies. Usually, big international corporations use these markets in order to hedge against future exchange rate fluctuations, but speculators take part in these markets as well.