Director Declaration

Serco Group plc (the Company or Serco)

Legal Entity Identifier: 549300PT2CIHYN5GWJ21

Director Declaration

The Company has been notified that John Rishton, Board Chair, will be appointed as a Non-Executive Director and member of the Audit and Nomination Committees of Diageo plc, with effect from 1 November 2025.

This announcement is made in accordance with Listing Rule 6.4.9(2).

Nickesha Graham-Burrell

Group Company Secretary

16 September 2025

For further information please contact:

Jamie Hastings, Group Head of Investor Relations, tel: +44 (0) 7738 897 268 or email:  [email protected]

Scot Marchbank, Group Communications and Marketing Director, tel: +44 (0) 7958 675 706 or email: [email protected]

About Serco

Serco brings together the right people, the right technology and the right partners to create innovative solutions that make positive impact and address some of the most urgent and complex challenges facing the modern world. With a primary focus on serving governments globally, Serco's services are powered by more than 50,000 people working across defence, space, migration, justice, healthcare, mobility and customer services. Serco's core capabilities include service design and advisory, resourcing, complex programme management, systems integration, case management, engineering, and asset & facilities management.

Underpinned by Serco's unique operating model, Serco drives innovation and supports customers from service discovery through to delivery. More information can be found at www.serco.com.