Athens, December 18, 2025 - Hellenic Telecommunications Organization S.A. ("OTE S.A." or the "Company") in relation to the distribution of an extraordinary dividend amounting to €0.10 gross per share after the sale of Telekom Romania Mobile Communications S.A., announces that:

The final dividend amount that will be paid out stands at €0.1019 gross per share, increased by the dividend corresponding to 7,405,921 own shares that will be held by the Company on December 22 2025 (ex-dividend date). The dividend is subject to a 5% withholding tax, in accordance with the applicable tax law provisions (art. 64 of Law 4172/2013 as in effect) with the exception or differentiation of such withholding for shareholders falling under special provisions. Therefore, the net amount of dividend which will be paid to Shareholders will be €0.096805 per share.

On Monday, December 22, 2025 the Company's shares will trade ex-dividend. Beneficiaries of the said dividend are the Shareholders registered in the Dematerialized Securities System (of the company "HELLENIC EXCHANGES S.A. HOLDING, CLEARING, SETTLEMENT & REGISTRY (HELEX)" on Tuesday December 23, 2025 (Record Date).

The payment of the dividend will be conducted on Tuesday, December 30, 2025 by "PIRAEUS BANK S.A.", as follows:

1.   Beneficiaries whose securities accounts are held with Banks or Investment Firms participating in the Dematerialized Security System (DSS) shall receive the dividend through their securities accounts, in accordance with the regulations in force of EL.K.AT.

2.   For dividends payable to the heirs of beneficiaries whose securities are held in the Special Account of the DSS, the dividend payment process will be carried out through the network of "Piraeus Bank SA", after the completion of the required legalization of the heirs. In case payment of dividends to the heirs of beneficiaries is not completed by the end of 2026, the payment process for the following years, up to the write-off, will be carried out directly by OTE S.A.

For any further Information, the Shareholders may contact the Investors Relations Department, e-mail: [email protected] [email protected]

Any dividends not be collected within 5 years, that is until 31-12-2030, will be written off in favor of the Hellenic State.

This announcement is issued in accordance with Law 3556/2007 and the Athens Exchange Regulation.

FOR FURTHER INFORMATION:

OTE GROUP INVESTOR RELATIONS

E-mail: [email protected]