> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/addressbase-plus/addressbase-plus-technical-specification/code-lists-and-enumerations.md).

# Code lists and enumerations

A code list or enumeration is a controlled set of values which can be used to populate a specific column. The code list and enumeration UML models associated with AddressBase Plus are shown in the diagram below:

<figure><img src="/files/dhn03FAgI6rz80oK7j9D" alt="Code lists and enumeration UML models represented in AddressBase Plus."><figcaption><p>Code list and enumeration UML models represented in AddressBase Plus.</p></figcaption></figure>

## AddressBase Plus code lists and enumerations

* [PostcodeTypeCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/postcodetypecode.md)
* [ChangeTypeCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/changetypecode.md)
* [OfficalFlagCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/officialflagcode.md)
* [USRNMatchIndicatorCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/usrnmatchindicatorcode.md)
* [RPCCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/rpccode.md)
* [StateCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/statecode.md)
* [LanguageCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/languagecode.md)
* [AddressbasePostalCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/addressbasepostalcode.md)
* [CountryCode](/os-downloads/products/addresses-and-names-portfolio/addressbase-fundamentals/code-lists-and-enumerations/countrycode.md)


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