The primary regions are designated as EU, EUN (EU Native), and UK, each with specific data centers serving respective geographical areas.

The following Webex Calling regions provide services for customers head-quartered in the EMEA region. All application regions are built and maintained to a common, state-of-the-art architecture.

Identifier	DC Locations	Description
EU	London & Frankfurt	The original region built to provide service for all customers across the EMEA region.
EUN	Frankfurt & Amsterdam	The new region provides service for all customers in the EMEA region, except the United Kingdom.
UK	London & Manchester	Region specifically for customers in the United Kingdom

When a new or existing customer first subscribes to Webex Calling, a Calling region is selected based on their headquarters location. Once assigned, it isn’t possible to change the customer’s Calling region. Ensure that the desired region is correctly selected when adding the Webex Calling service.

The following Calling region assignments are currently made when adding Webex Calling to a customer organization:

Headquarters Location	Webex Calling region assignment
Sites in the United Kingdom	UK
Sites in other European countries	EUN
Sites in Middle Eastern and African countries	EUN

Webex Calling data center assignment in Webex Calling is independent of data center assignment for common Webex services. When a customer organization is initially created, data centers providing common services, such as Identity, are assigned based on the business headquarters location. Refer to Administration - Data Residency in Webex for data center assignment for new Webex customers.

After the customer is created in Webex, they are assigned to a data center for the purpose of Webex Calling based on the preceding criteria.

For further details, see the Webex help articles on Data Residency in Webex and Data Center Assignments.