ISO 3166-2:SH is the entry for Saint Helena, Ascension and Tristan da Cunha in ISO 3166-2, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), which defines codes for the names of the principal subdivisions (e.g., provinces or states) of all countries coded in ISO 3166-1.
Currently for Saint Helena, Ascension and Tristan da Cunha, ISO 3166-2 codes are defined for 3 geographical entities.
Each code consists of two parts, separated by a hyphen. The first part is SH, the ISO 3166-1 alpha-2 code of Saint Helena, Ascension and Tristan da Cunha. The second part is two letters.
Ascension Island and Tristan da Cunha, previously dependencies of Saint Helena but raised to equal status in 2009, are exceptionally reserved the ISO 3166-1 alpha-2 codes AC and TA respectively on the request of the Universal Postal Union.