# AddressBase Products May 2026 – Epoch 127

## Record counts

<table><thead><tr><th width="169.6666259765625">Product</th><th>Full Supply Record Count</th><th>Change-Only Update Record Count</th></tr></thead><tbody><tr><td>OS Open UPRN</td><td>41 546 482</td><td>N/A</td></tr><tr><td>AddressBase</td><td>30 924 479</td><td>130 223</td></tr><tr><td>AddressBase Plus</td><td>38 743 686</td><td>849 637</td></tr><tr><td>AddressBase Premium</td><td>See rows below</td><td>See rows below</td></tr><tr><td>Street</td><td>1 526 341</td><td>16 251</td></tr><tr><td>Street Descriptor</td><td>1 650 670</td><td>5 027</td></tr><tr><td>BLPU</td><td>41 546 482</td><td>804 236</td></tr><tr><td>Classification</td><td>45 333 097</td><td>168 187</td></tr><tr><td>LPI</td><td>46 906 077</td><td>167 545</td></tr><tr><td>Organisation</td><td>1 389 164</td><td>16 417</td></tr><tr><td>Delivery Point Address</td><td>31 040 250</td><td>55 299</td></tr><tr><td>Application Cross Ref.</td><td>200 943 636</td><td>733 641</td></tr><tr><td>Successor</td><td>0</td><td>0</td></tr></tbody></table>

**Please note:**

* The Full Supply record counts are based on a Managed Great Britain Set (MGBS). If you have ordered your national coverage via the online ordering system using a polygon outline, then your counts may differ.
* Change-Only Updates (COUs) are not available for the OS Open UPRN product.

## Product supply comparison

There is a difference in product counts between taking a national Managed Great Britain Set (MGBS) and a national Area of Interest (AOI). This is because the two supplies use different selection criteria. The differences are shown in the following table, allowing for you to validate your data holdings once you have loaded the latest release of AddressBase data.

The national AOI refers to the pre-selection GB polygon from our download store. Therefore, if you have drawn your own AOI, the count will vary.

If you are unsure of your supply type, please check this with your OS Relationship Manager.

| Product                | MGBS Full Count | National AOI Full Count | Difference     |
| ---------------------- | --------------- | ----------------------- | -------------- |
| AddressBase            | 30 924 479      | 30 924 478              | 1              |
| AddressBase Plus       | 38 743 686      | 38 743 660              | 26             |
| AddressBase Premium    | See rows below  | See rows below          | See rows below |
| Street                 | 1 526 341       | 1 526 339               | 2              |
| Street Descriptor      | 1 650 670       | 1 650 668               | 2              |
| BLPU                   | 41 546 482      | 41 546 453              | 29             |
| Classification         | 45 333 097      | 45 333 066              | 31             |
| LPI                    | 46 906 077      | 46 906 047              | 30             |
| Organisation           | 1 389 164       | 1 389 162               | 2              |
| Delivery Point Address | 31 040 250      | 31 040 249              | 1              |
| Application Cross Ref. | 200 943 636     | 200 943 606             | 30             |
| Successor              | 0               | 0                       | 0              |

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](/os-downloads/products/addresses-and-names-portfolio/addressbase/addressbase-getting-started-guide/working-with-cou-data.md)' in the AddressBase Getting Started Guide.

## Changed records

If you receive a Change-Only Update (COU) supply for your AddressBase product, you will receive Insert, Update and Delete records within the supplied file. The following tables detail the numbers of these records which can be expected in an **MGBS supply**, and also how many tiles are affected if you take your supply as Changed Chunks.

### AddressBase

| Change Type              | Count  |
| ------------------------ | ------ |
| Inserts                  | 35 340 |
| Updates                  | 86 132 |
| Deletes                  | 8 751  |
| COU Populated Tile Count | 5 782  |

### AddressBase Plus

| Change Type              | Count   |
| ------------------------ | ------- |
| Inserts                  | 52 923  |
| Updates                  | 785 703 |
| Deletes                  | 15 141  |
| COU Populated Tile Count | 7 746   |

### AddressBase Premium

| AddressBase Premium Table | Inserts | Updates | Deletes |
| ------------------------- | ------- | ------- | ------- |
| Street                    | 1 414   | 14 757  | 80      |
| Street Descriptor         | 1 456   | 3 491   | 80      |
| BLPU                      | 44 268  | 745 821 | 5 147   |
| Classification            | 55 960  | 95 212  | 17 015  |
| LPI                       | 57 022  | 104 141 | 6 382   |
| Organisation              | 7 085   | 5 047   | 4 285   |
| Delivery Point Address    | 35 789  | 11 072  | 8 438   |
| Application Cross Ref.    | 0       | 0       | 0       |

## Source data currency

The following information relates to the currency of the source data used in the creation of Epoch 127:

| Data Source                          | Date            |
| ------------------------------------ | --------------- |
| Royal Mail PAF                       | 09 April 2026   |
| National Land and Property Gazetteer | 09 April 2026   |
| One Scotland Gazetteer               | 22 March 2026   |
| VOA Non-Domestic Rates               | 07 April 2026   |
| VOA Council Tax                      | 07 April 2026   |
| OS MasterMap Topography Layer        | 31 March 2026   |
| OS MasterMap Highways Network        | 08 April 2026   |
| Code-Point with Polygons             | 01 April 2026   |
| Boundary-Line                        | 02 October 2025 |

## Data issues

### AddressBase

Details of live and resolved data issues for AddressBase will be communicated on the [AddressBase Known Data Issues page](/os-downloads/products/addresses-and-names-portfolio/addressbase/addressbase-known-data-issues.md). This page will provide details of their impacts and updates on the expected time frame for their resolution.

### AddressBase Plus issues

Details of live and resolved data issues for AddressBase Plus will be communicated on the [AddressBase Plus Known Data Issues page](/os-downloads/products/addresses-and-names-portfolio/addressbase-plus/addressbase-plus-known-data-issues.md). This page will provide details of their impacts and updates on the expected time frame for their resolution.

### AddressBase Premium

Details of live and resolved data issues for AddressBase Premium will be communicated on the [AddressBase Premium Known Data Issues, Service Disruptions and Planned Maintenance page](/os-downloads/products/addresses-and-names-portfolio/addressbase-premium/addressbase-premium-known-data-issues-service-disruptions-and-planned-maintenance.md). This page will provide details of their impacts and updates on the expected time frame for their resolution.

## Improvements in Epoch 127

### Valuation Office Agency matching

The match rates for Council Tax and Non-Domestic Rates for Epoch 127 are detailed as follows based on Valuation Office Agency (VOA) records up to 07 April 2026. The match rate is applicable to the AddressBase Premium product.

| Data Source        | Records Received | % Matched |
| ------------------ | ---------------- | --------- |
| Council Tax        | 27 453 896       | 99.89     |
| Non-Domestic Rates | 2 130 117        | 96.41     |

## Next release

The next release of AddressBase products, Epoch 128, is scheduled for **25 June 2026.**


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