---
description: >-
  This release note provides information about the release of the AddressBase
  Core product on 17 June 2025.
---

# 17 June 2025

## Record counts

<table><thead><tr><th width="238">Product</th><th>Full Supply Record Count</th><th>Change-Only Update Record Count</th></tr></thead><tbody><tr><td>AddressBase Core</td><td>34 660 548</td><td>65 656</td></tr></tbody></table>

{% hint style="info" %}
Please note that the Full Supply record count is based on a Managed Great Britain Set (MGBS). If you ordered your national coverage via the online ordering system using a polygon outline, your counts may differ.
{% endhint %}

## Product supply comparison

There is a difference in record counts between taking a national Managed Great Britain Set (MGBS) and the national 5km-tile supply. This is because the two supplies use different selection criteria. The difference in record counts is shown in the following table, allowing you to validate your data holdings once you have loaded the latest release of AddressBase Core.

| Product          | MGBS Full Count | National 5km Tiled Supply | Difference |
| ---------------- | --------------- | ------------------------- | ---------- |
| AddressBase Core | 34 660 548      | 34 660 538                | 10         |

A small difference in record counts is expected due to there being several features supplied in the MGBS which fall outside of the tiled area.

## Changed records

If you receive a Change-Only Update (COU) supply for your AddressBase Core product, you will receive Insert, Update and Delete records within the supplied file. The following table details the numbers of these records which can be expected in the COU supply of the product:

| Change Type                  | Count  |
| ---------------------------- | ------ |
| Inserts                      | 7 809  |
| Updates                      | 54 568 |
| Deletes                      | 2 279  |
| COU populated 5km tile count | 3 701  |

It's important that COUs are processed with Deletes first, then Inserts and Updates. This is to ensure that updates are applied in the correct order. Further guidance on this can be found in '[Working with COU data](https://docs.os.uk/os-downloads/addressing-and-location/addressbase/addressbase-getting-started-guide/working-with-cou-data)' in the AddressBase Getting Started Guide.

## Source data currency

The following information relates to the currency of the source data used in the creation of this release of AddressBase Core:

<table><thead><tr><th width="384">Data Source</th><th>Date</th></tr></thead><tbody><tr><td>Royal Mail Postcode Address File (PAF)</td><td>13 June 2025</td></tr><tr><td>National Land and Property Gazetteer</td><td>13 June 2025</td></tr><tr><td>One Scotland Gazetteer</td><td>02 June 2025</td></tr><tr><td>OS MasterMap Topography Layer</td><td>22 May 2025</td></tr></tbody></table>

## Known data issues

Details of data issues for AddressBase Core will be communicated on the [AddressBase Core Known Data Issues page](../addressbase-core-data-issues-service-disruptions-and-planned-maintenance). This page will provide details of the impacts of any data issues, plus updates on the expected time frame for resolution.
