Hellenic Telecommunications Organization S.A.

Transaction in Own Shares • Dec 15, 2025

Announcement Purchase of Own Shares

Athens, December 15, 2025 – Hellenic Telecommunications Organization S.A, ("OTE" or the "Company"), announces that, during 08/12/2025 – 12/12/2025, it purchased 241,399 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 (€)
8/12/2025	43,711	759,009.43	17.36427	17.31	17.42
9/12/2025	52,625	911,092.60	17.31292	17.25	17.43
10/12/2025	74,441	1,279,496.48	17.18806	17.15	17.22
11/12/2025	41,031	705,227.58	17.18770	17.15	17.22
12/12/2025	29,591	509,348.59	17.21300	17.17	17.24
Total	241,399	4,164,174.68	17.25017

Following this, the Company holds 7,106,332 own shares or 1.760% 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