AddressBase Products May 2026 – Epoch 127

This release note provides information about the May 2026 (Epoch 127) release of the AddressBase products. These products were released to customers on 14 May 2026.

Record counts

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

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' 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	754 821	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.	207 708	487 396	38 537

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. 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. 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. 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.