# SubdivisionCode - `v::subdivisionCode(string $countryCode)` Validates subdivision country codes according to [ISO 3166-2][]. The `$countryCode` must be a country in [ISO 3166-1 alpha-2][] format. ```php v::subdivisionCode('BR')->validate('SP'); // true v::subdivisionCode('US')->validate('CA'); // true ``` This rules uses data from [iso-codes][]. *** See also: * [CountryCode](CountryCode.md) * [CurrencyCode](CurrencyCode.md) * [IdentityCard](IdentityCard.md) * [KeyValue](KeyValue.md) * [Tld](Tld.md) [iso-codes]: https://salsa.debian.org/iso-codes-team/iso-codes [ISO 3166-1 alpha-2]: http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 "ISO 3166-1 alpha-2" [ISO 3166-2]: http://en.wikipedia.org/wiki/ISO_3166-2 "ISO 3166-2"