C2 General Dated: 13 June 2023 VODAFONE GROUP PUBLIC LIMITED COMPANY and Margherita Della Valle SERVICE AGREEMENT Exhibit 4.21

EXECUTED as a DEED on behalf of VODAFONE GROUP PUBLIC LIMITED COMPANY /s/ Leanne Wood Leanne Wood /s/ James Ludlow Name: James Ludlow Occupation: Group Reward & Policy Director, VGSL EXECUTED as a DEED by /s/ Margherita Della Valle Margherita Della Valle /s/ Geraldine McTaggart Name: Geraldine McTaggart Occupation: Personal Assistant to Group CEO 17