> For the complete documentation index, see [llms.txt](https://docs.os.uk/osngd/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/osngd/data-structure/address/address-related-components/other-alias.md). # Other Alias The Other Alias Component provides alternate names for counties, localities and thoroughfares. County aliases provide alternate names for a county, including Traditional, Administrative and Former Postal County information. Locality aliases include old short-form names, local names and Postally Not Required (PNR) Localities. Thoroughfare Alias information provides replacement Thoroughfare names for a given Locality, Thoroughfare or Dependent Thoroughfare combination. For more information about components of the Other Alias table, please consult chapter six 'Alias' of the [Royal Mail Programmer's Guide](https://www.poweredbypaf.com/resources/). {% hint style="info" %} ### Other Alias Component for Royal Mail Address Feature Type data schema version 2.0 onward Customers taking data schema version 2.0 onward of the Royal Mail Address Feature Type in GeoPackage format will receive the following in their data package: * **Feature type:** Royal Mail Address * **Related components:** Multiple Residence, Delivery Point Alias and Other Alias However, the three related components (Multiple Residence, Delivery Point Alias and Other Alias) will only be provided for Royal Mail Address features if the Description attribute is 'Postcode Address File'. Against all other Royal Mail Address features, the related components will be populated as null. Please note that the **Delivery Point Alias and Other Alias Related Component** tables are included in product design for future compatibility but are **not currently populated**; customers should expect these files to be empty until a future data enhancement enables OS to supply the Royal Mail alias data. Please see the [FAQs](/osngd/getting-started/faqs.md#why-are-the-other-alias-and-delivery-point-alias-related-component-tables-in-my-royal-mail-address-f) for more information. {% endhint %} ## Temporal filtering The earliest date on which you can request a one-off snapshot of a date in the past for data in this feature type is 08 October 2026. Any data temporally filtered earlier than the specified earliest date noted above for the data schema version may contain data inconsistencies. More information about temporal filtering is available from the [Getting started with temporal filtering guide](/osngd/getting-started/downloading-with-os-select+build/getting-started-with-data-packages/getting-started-with-temporal-filtering.md). ## Related component attributes The following sub-sections provide details about the attributes included with this related component, their data types in the different output formats, and other important metadata about them. ### aliasid Ordnance Survey derived primary key providing a unique row identifier assigned to enable indexing for efficient querying. * **Data Types:** String (GPKG), String (CSV) * **Nullable:** false * **Max Length:** 36 * **OS Select+Build Filterable:** No * **Data Schema Version:** 2.0 ### udprn Unique Delivery Point Reference Number (UDPRN) assigned by Royal Mail as a persistent identifier, belonging to the feature of which the alias relates to. * **Data Types:** Integer (GPKG), Integer (CSV) * **Nullable:** false * **OS Select+Build Filterable:** No * **Data Schema Version:** 2.0 ### featuretypeversiondate Date of the feature version to which this related component applies. This is used along with the Feature Type ID attribute to join the component to the Royal Mail Address Feature Type. * **Data Types:** Date (GPKG), Date (CSV) * **Nullable:** false * **OS Select+Build Filterable:** No * **Data Schema Version:** 2.0 ### alias Contains alias name text, derived from either Thoroughfare, Locality or County source tables. * **Data Types:** String (GPKG), String (CSV) * **Nullable:** false * **Max Length:** 150 * **OS Select+Build Filterable:** No * **Data Schema Version:** 2.0 ### aliasrecordtype Indicates the source alias table from which the record has been derived. * **Data Types:** String (GPKG), String (CSV) * **Nullable:** false * **Max Length:** 25 * **OS Select+Build Filterable:** No * **Data Schema Version:** 2.0 ### aliastype Indicates the alias subdivision applicable to the record. * **Data Types:** String (GPKG), String (CSV) * **Nullable:** false * **Max Length:** 30 * **OS Select+Build Filterable:** No * **Data Schema Version:** 2.0 ### aliascode Royal Mail raw alias component information, containing concatenated components and codes as a single string attribute. * **Data Types:** String (GPKG), String (CSV) * **Nullable:** false * **Max Length:** 150 * **OS Select+Build Filterable:** No * **Data Schema Version:** 2.0 --- # Agent Instructions This documentation is published with GitBook. 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