ISO 3166-2:TD is the entry for Chad 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 Chad, ISO 3166-2 codes are defined for 23 provinces (mintaqah[1]).
Each code consists of two parts, separated by a hyphen. The first part is TD, the ISO 3166-1 alpha-2 code of Chad. The second part is two letters.