ISO 4217 Currency Codes Explained: Letters, Numbers, Decimals and Changes

What ISO 4217 covers

ISO 4217 gives every currency a three-letter code, a three-digit number and a "minor unit" value that says how many decimal places it uses. The first edition appeared in 1978 and the current edition is ISO 4217:2015, but the code lists themselves change between editions. They are maintained by SIX, the Swiss financial infrastructure company, on behalf of ISO and the Swiss Association for Standardization (SNV). SIX publishes three lists: List One for current currencies and funds, List Two for fund codes and List Three for historic codes.

List One, as published on 1 January 2026, holds 178 codes. Of those, 159 are national currencies or national fund codes, and 19 start with X. Every Beelad country page shows its currency's ISO code; the Japan page, for example, shows the yen as JPY.

How the letter codes are built

For a national currency, the first two letters are usually the country's ISO 3166-1 alpha-2 code and the third is usually the first letter of the currency's name: JPY is Japan's yen, CHF the Swiss franc, INR the Indian rupee. ISO describes this as the typical pattern, not a strict rule. In the January 2026 list, 158 of the 159 non-X codes begin with a current ISO country code. The exception is EUR, which uses EU, a code ISO 3166 reserves for the European Union but does not assign as a country.

The X codes

Codes starting with X are for things that are not one country's currency. ISO 3166 never assigns country codes beginning with X, so they cannot clash.

• Shared regional currencies: XOF (West African CFA franc, 952), XAF (Central African CFA franc, 950), XCD (East Caribbean dollar, 951), XPF (CFP franc, 953) and the newest, XCG (Caribbean guilder, 532) for Curaçao and Sint Maarten.
• Precious metals: XAU gold (959), XAG silver (961), XPT platinum (962), XPD palladium (964).
• Accounting units: XDR for the IMF's Special Drawing Right (960) and XAD, the Arab Monetary Fund's Arab Accounting Dinar (396), added in May 2025.
• Technical codes: XTS (963) is reserved for testing, and 999 is the numeric code for transactions where no currency is involved.

The numeric codes

Numeric codes help systems that cannot handle Latin letters. A national currency usually takes its country's ISO 3166 numeric code: the US dollar is 840, like the United States, and the Swiss franc is 756, like Switzerland. In the 2026 list, 118 of the 159 non-X codes share a number with a current country code. The others are worth knowing, because they are where copy-paste errors happen:

• Brazil: the real is BRL 986. The number 086 is the country code of the British Indian Ocean Territory, and some older tables wrongly give it for BRL. Brazil's own country number is 076.
• New currencies get new numbers: the Turkish lira since 2005 is 949 (Türkiye is 792), and Zimbabwe's ZiG is 924 (Zimbabwe is 716). Not always, though: the Caribbean guilder kept 532, the number of the Netherlands Antillean guilder it replaced.
• Old numbers can outlive their country code: the Ethiopian birr is still 230, Ethiopia's country number before Eritrea split off in 1993; Ethiopia itself is now 231. The Panamanian balboa is 590, Panama's withdrawn country number; the country is now 591.
• Supranational: the euro is 978.

Minor units: the field that breaks payments

Each code has a minor-unit value, the number of digits after the decimal point. Most currencies use 2, but not all, and the difference matters whenever amounts are stored as whole numbers of the smallest unit, as most payment systems do.

Two currencies are special: the Mauritanian ouguiya and the Malagasy ariary are divided into five subunits, not 100, but ISO lists both with a minor unit of 2.

Shared currencies

Many countries use a currency they do not issue alone. Among Beelad's 196 countries, 27 use the euro, 8 use the West African CFA franc (issued by the BCEAO), 6 use the Central African CFA franc (BEAC), 6 use the East Caribbean dollar and 4 use the Australian dollar, including Tuvalu. Seven list the US dollar, the United States plus six countries that adopted it.

The euro area itself has grown in steps. Bulgaria became its 21st member on 1 January 2026, at a fixed rate of 1.95583 lev per euro, so 100 lev became €51.13. The lev and the euro circulated together only during January 2026. ISO moved BGN (numeric 975) to the historic list, and Croatia's kuna (HRK) went the same way when Croatia joined on 1 January 2023 at 7.53450 kuna per euro.

Why codes change

A currency usually gets a new code when it is redenominated, meaning zeros are removed and old notes are exchanged at a fixed ratio. This lets systems tell old amounts from new ones.

Zimbabwe's case shows how quickly this can happen. The ZiG ("Zimbabwe Gold") was announced on 5 April 2024 and became the official currency on 8 April, but ISO only added ZWG in Amendment 177 on 20 June 2024. For more than two months, systems had no official code for it.

Currency symbols are not part of ISO 4217

ISO 4217 defines codes, not symbols. Symbols are set by central banks and encoded by Unicode, and they also change:

• Saudi riyal: the Saudi Central Bank adopted a new official symbol on 20 February 2025. Unicode added it as U+20C1 SAUDI RIYAL SIGN in Unicode 17.0, released on 9 September 2025. The older ﷼ (U+FDFC) is a generic "rial" ligature.
• UAE dirham: the Central Bank of the UAE unveiled a new dirham symbol on 27 March 2025, and it was encoded as U+20C3 in Unicode 18.0, reported in September 2026. Until fonts catch up, the abbreviation د.إ remains common.

Because fonts and keyboards lag behind, the ISO code (SAR, AED) is the safest thing to show in data exports and invoices.

Key takeaways

• ISO 4217 List One had 178 codes in January 2026; 19 start with X.
• Letter codes usually start with the ISO country code; EUR and the X codes are the main exceptions.
• Numeric codes usually match the country number, but not always: BRL is 986, not 086.
• Minor units range from 0 (JPY) to 4 (CLF). Never assume 2.
• Codes change with redenominations and euro adoption: BGN was withdrawn on 1 January 2026, and ZWL was replaced by ZWG in 2024.