Hellenic Telecommunications Organization S.A.

Transaction in Own Shares • Dec 19, 2025

Announcement Purchase of Own Shares

Athens, December 19, 2025 – Hellenic Telecommunications Organization S.A, ("OTE" or the "Company"), announces that, during 15/12/2025 – 18/12/2025, it purchased 299,589 own shares, in the context of the Own Share Buy Back Programme for 2025, as follows:

Date	Number of shares	Total amount (€)	Average price (€)	Lowest price (€)	Highest price (€)
15/12/2025	60,634	1,040,161.00	17.15470	17.06	17.23
16/12/2025	90,231	1,529,195.85	16.94760	16.85	17.08
17/12/2025	98,009	1,639,446.46	16.72751	16.58	16.97
18/12/2025	50,715	852,847.88	16.81648	16.76	16.99
Total	299,589	5,061,651.19	16.89532

Following this, the Company holds 7,405,921 own shares or 1.834% of the total outstanding shares.

The announcement is issued in accordance with Regulation (EU) No 596/2014 of the European Parliament and of the Council of 16 April 2014 and the Commission Delegated Regulation (EU) 2016/1052 of 8 March 2016.

FOR FURTHER INFORMATION:

OTE GROUP INVESTOR RELATIONS Τel. +30 210 6117364, +30 210 6332342 E-mail: iroffice@ote.gr, eboua@ote.gr