Hellenic Telecommunications Organization S.A.

Transaction in Own Shares • Sep 15, 2025

Announcement Purchase of Own Shares

Athens, September 15, 2025 – Hellenic Telecommunications Organization S.A, ("OTE" or the "Company"), announces that, during 08/09/2025 – 12/09/2025, it purchased 69,880 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 (€)
8/9/2025	19,145	310,528.77	16.21984	16.13	16.29
9/9/2025	27,499	446,859.19	16.25002	16.11	16.29
10/9/2025	16,949	276,186.21	16.29513	16.20	16.37
11/9/2025	4,906	81,094.89	16.52974	16.50	16.57
12/9/2025	1,381	22,972.13	16.63442	16.61	16.73
Total	69,880	1,137,641.19	16.27993

Following this, the Company holds 4,328,815 own shares or 1.072% 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