Working in GIS and mapping areas or assets across the United Kingdom and Ireland means you’ve likely heard of British National Grid (BNG), WGS1984 or the Irish Grid coordinate reference systems. Another coordinate system you may be using, perhaps without realising it, is the European Terrestrial Reference System 1989 (ETRS89). If you do use this coordinate system (or perhaps need to pause reading this blog to check if you do), then with future ArcGIS releases you may notice some changes to how ETRS89 coordinate systems are named and identified.
The good news is that, for most ArcGIS users, there is no immediate action. But in this blog, you can learn all you need to know – from what is changing, to when it’s changing, how it might impact your data and what actions you may need to take in the future. Let’s get stuck in.
At a glance
The ETRS89 coordinate reference system is being updated to country-specific realisations and identifiers such as ETRS89-GBR and ETRS89-IRE. Existing coordinate system definitions remain valid, while users will begin seeing new names and identifiers for ETRS89, aligned with updated standards.
Existing datasets, maps, services, and workflows will continue to work without modification.
British National Grid and Irish Grid are not affected by these changes.
Future ArcGIS releases will adopt the updated EPSG naming conventions while maintaining compatibility with existing content.
What’s changing?
The changes are driven by updates to the EPSG Geodetic Registry, the internationally recognised authority for coordinate reference systems. As ArcGIS continues to align with industry standards, Esri is incorporating these updates into future releases of the platform.
The main change is that ETRS89 will begin appearing as country-specific realisations with associated EPSG identifiers. For example:
- ETRS89-GBR [OSNet v2009] (EPSG::11009) will become the recognised name for Great Britain and Isle of Man’s ETRS89 coordinate system.
- ETRS89-IRE [ETRF2000] (EPSG::4173) will become the recognised name for Ireland’s ETRS89 coordinate system.
- And so on…
This update relates primarily to how ETRS89 coordinate systems are identified within geospatial software. The objective is to provide greater clarity and consistency across the geospatial industry by identifying the country-specific realisations of ETRS89 used across Europe.
Will this affect my existing GIS data?
For the vast majority of users, no.
Existing datasets, maps, feature services, geoprocessing workflows, applications and projects will continue to operate without modification. Future ArcGIS releases will continue to recognise existing coordinate system definitions while also displaying the new identifiers and aliases where appropriate. No migration of existing content is required.
If you are considering adopting the new identifiers, you should first understand any workflow dependencies and manage any changes through appropriate change management practices.
What about British National Grid?
One of the most common questions from UK GIS users is whether British National Grid (BNG) (EPSG:27700) is changing as part of this update. The answer is no. BNG remains the standard projected coordinate system used across Great Britain and Isle of Man and is not being renamed as part of these EPSG changes. Organisations that use BNG for mapping, asset management, planning, or operational workflows can continue to do so exactly as they do today.
What about transformations?
Some advanced GIS workflows rely on transformations between ETRS89 and other coordinate reference systems. Existing transformation accuracy and results are not changing as a result of these updates. However, users may begin seeing new country-specific ETRS89 identifiers and associated transformations appear as ArcGIS aligns with updated EPSG standards.
Organisations considering adoption of the new identifiers should validate workflows and connected systems before implementation.
What is the impact on ArcGIS?
ArcGIS Pro
Existing ArcGIS Pro projects will continue to function normally. Users may begin to see the updated ETRS89 identifiers when creating new datasets, defining coordinate systems, or reviewing spatial reference properties from ArcGIS Pro 3.8.
ArcGIS Enterprise
Existing services, applications, and integrations will continue to function normally. ArcGIS Enterprise 12.2 will recognise the updated ETRS89 identifiers while maintaining compatibility with existing content.
ArcGIS Online
Existing hosted data, web maps and applications are not expected to require any changes because of this update.
Support for the new ETRS89 identifiers will be introduced across the ArcGIS platform over time. Organisations considering adoption of the new identifiers should validate their workflows and connected systems before implementation.
What do I need to do?
For most organisations, no immediate action is required.
If you use ETRS89, conduct appropriate due diligence across your GIS estate before adopting the new country-specific identifiers. Organisations should check that workflow dependencies, integrations, applications, services, and data exchange processes can correctly recognise and process the new identifiers is required.
Taking this approach now will help maintain compatibility while allowing you to align with evolving industry standards.
The bottom line
The upcoming EPSG updates introduce new country-specific ETRS89 identifiers aligned with evolving industry standards.
Existing content will continue to work as it does today and no migration of data, maps, services or applications is required. For most users, the only noticeable change will be seeing new ETRS89 names and identifiers when creating or managing content.
Organisations adopting the new identifiers should validate dependent systems and workflows before implementation.