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.
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.
