ISO 4217 Currency Code Standard — Complete Overview

Understanding ISO 4217

ISO 4217 is the international standard published by the International Organization for Standardization (ISO) that defines codes for the representation of currencies and funds. First published in 1978, it has become the universal standard for identifying currencies in banking, finance, and software systems worldwide.

Structure of ISO 4217

Each currency in the standard is assigned:

• Alphabetic code — A three-letter code (e.g., USD, EUR, JPY). The first two letters usually correspond to the ISO 3166-1 alpha-2 country code, and the third letter is typically the initial of the currency name.
• Numeric code — A three-digit code (e.g., 840 for USD, 978 for EUR). This is useful in systems that don't support alphabetic characters.
• Minor unit — The number of decimal places used (e.g., 2 for USD cents, 0 for JPY, 3 for KWD fils).

Code   Num   Name                Minor Unit
USD    840   US Dollar           2
EUR    978   Euro                2
JPY    392   Japanese Yen        0
KWD    414   Kuwaiti Dinar       3

Code Assignment Rules

The alphabetic codes follow specific patterns:

• Country currencies: First two letters = ISO 3166-1 country code. Example: USD (United States + Dollar), GBP (Great Britain + Pound), JPY (Japan + Yen)
• Supranational: Codes starting with X are reserved for non-country entities. XAU (gold), XAG (silver), XDR (IMF SDR)
• Testing: XTS is reserved for testing, XXX for "no currency"

Maintenance

The standard is maintained by SIX Interbank Clearing on behalf of ISO. Amendments are published when currencies are introduced (e.g., South Sudan Pound, SSP, in 2011), replaced (Croatian Kuna HRK replaced by EUR in 2023), or when minor unit definitions change. The current edition is ISO 4217:2015 with ongoing amendments.