AddressBase Products April 2026 – Epoch 126

This release note provides information about the April 2026 Epoch 126 release of the AddressBase products. These products were released to customers on 02 April 2026.

Record counts

Product	Full Supply Record Count	Change-Only Update Record Count
OS Open UPRN	41 507 361	N/A
AddressBase	30 897 890	138 295
AddressBase Plus	38 706 709	733 300
AddressBase Premium	See rows below	See rows below
Street	1 525 007	16 118
Street Descriptor	1 649 294	2 502
BLPU	41 507 361	655 949
Classification	45 294 152	165 924
LPI	46 855 437	175 454
Organisation	1 386 364	14 108
Delivery Point Address	31 012 899	63 989
Application Cross Ref.	200 774 465	620 825
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	30 897 890	30 897 889	1
AddressBase Plus	38 706 709	38 706 682	27
AddressBase Premium	See rows below	See rows below	See rows below
Street	1 525 007	1 525 004	3
Street Descriptor	1 649 294	1 649 291	3
BLPU	41 507 361	41 507 331	30
Classification	45 294 152	45 294 120	32
LPI	46 855 437	46 855 406	31
Organisation	1 386 364	1 386 362	2
Delivery Point Address	31 012 899	31 012 898	1
Application Cross Ref.	200 774 465	200 774 434	31
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	34 944
Updates	92 168
Deletes	11 183
COU Populated Tile Count	5 198

AddressBase Plus

Change Type	Count
Inserts	55 006
Updates	671 373
Deletes	13 152
COU Populated Tile Count	7 080

AddressBase Premium

AddressBase Premium Table	Inserts	Updates	Deletes
Street	1 068	14 989	61
Street Descriptor	1 107	1 331	64
BLPU	45 018	607 147	3 784
Classification	56 866	87 934	21 124
LPI	57 671	112 787	4 996
Organisation	4 349	5 194	4 565
Delivery Point Address	35 532	17 075	11 382
Application Cross Ref.	205 091	379 576	36 158

Source data currency

The following information relates to the currency of the source data used in the creation of Epoch 126:

Data Source	Date
Royal Mail PAF	26 February 2026
National Land and Property Gazetteer	26 February 2026
One Scotland Gazetteer	08 February 2026
VOA Non-Domestic Rates	24 February 2026
VOA Council Tax	24 February 2026
OS MasterMap Topography Layer	17 February 2026
OS MasterMap Highways Network	05 February 2026
Code-Point with Polygons	02 January 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 126

Valuation Office Agency matching

The match rates for Council Tax and Non-Domestic Rates for Epoch 126 are detailed as follows based on Valuation Office Agency (VOA) records up to 24 February 2026. The match rate is applicable to the AddressBase Premium product.

Data Source	Records Received	% Matched
Council Tax	27 423 462	99.89
Non-Domestic Rates	2 125 966	96.44

Tertiary classifications

Work is being undertaken to improve the classifications of records within the AddressBase products. This work has resulted in 45 684 more tertiary classifications present in Epoch 126 compared to Epoch 125. Indeed, 87.99 % of these tertiary classification improvements are against residential codes.

Next release

The next release of AddressBase products, Epoch 127, is scheduled for 14 May 2026.