The ISO currently provides three-letter currency codes for most of the world's currency. These codes combine the two-letter alphabetic codes (US for United States) for each country with the first letter of the currency (D for Dollar) to create the code for the US Dollar (USD). We use the ISO three-letter currency codes whenever one has already been established by the ISO. In creating new codes, we follow their methodology of combining the first two-letters of the country with a code for the currency.
In order for the ISO to create a currency code, the agency issuing the currency must apply for a code. Some countries, for political or economic reasons, have issued currencies, but failed to apply for a code. Transdiniestra has been issuing its own Ruble banknotes since 1993, but because it is not internationally recognized has never applied for an ISO country or currency code. Similarly, Yugoslavia was under international sanctions when it issued new versions of the Dinar in October 1993 and January 1994. Both currencies were short-lived, and never received ISO codes. Of the six currencies Yugoslavia has had since 1989, only three have been assigned ISO codes.
Another set of currency codes was created by RINET (the Reinsurance and Insurance Network) though they never received ISO 4217 approval. To avoid confusion, the ISO does not plan to replicate any of the RINET codes. We have included the RINET codes in the lists for each country for reference purposes, but we put an asterisk next to the codes, e.g. (BJK*), to differentiate them from our own codes and from those of the ISO.
We provide both three-letter codes and four-letter codes for currencies. The three-letter codes are provided for currencies that have been issued by countries that are still in existence or have had a two-letter code assigned to them by the ISO. The Rhodesia Pound has been given the symbol RHP because Rhodesia was assigned the symbol RH by the ISO, but the Katanga Franc has been assigned the symbol KATF because Katanga never received an ISO code.
One way in which our country codes differ from the ISO is that we provide some four-letter codes for historic currencies. There are several reasons for this.
First, four-letter codes are provided for the currencies of "dead" countries. Hence, the Confederate States of America (CSA) Dollar has been given the code CSAD to indicate that the Confederate States no longer exists; however, the United States Paper Dollar, which circulated between 1862 and 1878, has been given the code USP to differentiate it from the Gold Dollar (USD).
Second, four-letter codes are provided for special versions of existing currencies. This differs from the ISO methodology because they use three-letter codes for special currencies. For example, South Africa had a Financial Rand from 1985 to 1995, which could only be used for buying and selling financial assets in South Africa. The ISO gave the South African Financial Rand the code ZAL (as opposed to ZAR for the South African Rand). We give the South African Financial Rand the code ZARL, with the suffix "L" added to indicate the Financial version of the Rand.
When two currencies exist at different points in time, it is obvious that they are different currencies, but what should be done when a country has two currencies - paper and gold Dollars, or Spot and Financial Rands? The primary rule we use for differentiating between which currency variations should receive three-letter codes and which should receive four-letter codes is whether the currency existed in physical form or not.
The United States Paper Dollar was a separate currency from the Gold Dollar and the two fluctuated in value against one another. The Financial Rand was not a separate currency from the physical Rand, but was a way that the South African government could reduce the loss of foreign currency from repatriation. The same rule applies to the special currencies introduced by the Nazis during World War II.
The reason for using a four-letter code instead of a three-letter code is that we think it is important to differentiate between currencies that exist at different points in time, and special government created currencies that exist at one point in time. This avoids confusion that might otherwise exist.
For example, let's say that Mexico had special exchange rates for financial transactions both for the old Peso (MXP) and for the new Peso (MXN). The ISO's system could not differentiate between these two financial Pesos, but our system could differentiate between them by assigning the codes MXPL for the financial version of the old Peso and MXNL for the financial version of the New Peso.
Third, four-letter codes are provided for international currencies that no longer exist. For example, the East Africa Shilling (XEAS) was used in a number of countries in Africa and the Middle East while they were British colonies or protectorates. This followed the British policy of trying to minimize the number of colonial currencies. Once these countries gained their independence, they replaced the East Africa Shilling with their own domestic currencies.
Fourth, four-letter codes are used for monetary systems that were used within a nation, but for which there were a multitude of local issuers of that currency. The German Convention Thaler (XDCT) was a monetary standard used in Germany in the Eighteenth Century. Although different principalities and bishoprics issued their own coins, each tried to adhere to the standard laid down by the Convention of Vienna in 1753.