AddressBase Core Data Issues, Service Disruptions and Planned Maintenance
This page provides the details of known data issues and service disruptions impacting the AddressBase Core product. It also provides information on any planned maintenance periods.
Live known data issues
There are no live known data issues for AddressBase Core at this time.
Resolved data issues
Incorrect GSS code values for address records in Sheffield and Barnsley
The AddressBase Core product refresh scheduled for the week commencing 11 August 2025 only contained changes to correct the GSS (Government Statistical Service) codes for Sheffield and Barnsley. Changes from Local Authorities, Royal Mail or Ordnance Survey were not available in that week's product refresh.
The AddressBase Core product refresh scheduled for the week commencing 19 August 2025 successfully included two weeks’ worth of change from Local Authorities, Royal Mail and Ordnance Survey.
An issue was encountered following the change in GSS codes for Sheffield and Barnsley that took effect on 01 April 2025. This has resulted in AddressBase Core currently displaying the historic GSS code.
The previous and current GSS code changes as of 01 April 2025 are detailed in the table below:
Local Authority District
Current AB Core (historic) GSS Code
Correct GSS Code
(Effective from 01 April 2025)
Barnsley
E08000016
E08000038
Sheffield
E08000019
E08000039
GSS code fix planned for the week commencing 11 August 2025, with full implementation during the week commencing 19 August 2025.
10/06/2025 – Under investigation 12/08/2025 – Fix successfully implemented and released week commencing 11/08/2025.
19/08/2025 – This week's release contained all previously suspended updates.
Service disruption
There are no live service disruptions affecting AddressBase Core at this time.
Planned maintenance
Planned maintenance starting: Week beginning Monday 29 December 2025
Disruption description
Planned maintenance is scheduled for the AddressBase Core Product from the week beginning Monday 29 December 2025
Impacts of the disruption
During the maintenance period there will be no changes available in AddressBase Core for the product refresh planned for the week commencing 29 December. All daily Change Only Update (COU) orders will continue to be delivered and processed as usual. Customers who have Change Only Update orders will receive empty files during the maintenance period.
Changes will resume from the AddressBase Core product refresh scheduled for the week commencing 5th January 2026 and will include 2 weeks’ worth of change.
When to expect the next update
We will keep you informed of any changes to this schedule and provide updates as needed.
Last updated
Was this helpful?