NOS SGPS

Capital/Financing Update • Jul 26, 2024

NOS, SGPS, S.A. Registered Office: Rua Ator António Silva 9 – Campo Grande 1600-404 Lisbon Share Capital: 855,167,890.80 Euros Registered in the Commercial Registry Office of Lisbon and Corporation no. 504 453 513

ANNOUNCEMENT

Fitch affirms NOS at "BBB" issuer credit rating

Lisbon, 26 july 2024 - Pursuant to the terms and for the purposes of nr. 3 of article 29ºQ of the Portuguese Securities Code and article 17º of Regulation nr. 596/2014 of the European Parliament and Council, NOS, SGPS, S.A. ("NOS") hereby informs:

Fitch Ratings (Fitch) has affirmed NOS' Long Term Issuer Default Rating at "BB" with a Stable Outlook.

According to Fitch, NOS's rating reflects its "established market positions and robust financial performance. Fitch also anticipates that NOS will "continue improving its pre-dividend cash flow generation" while maintaining its comfortable leverage.

Maintaining this investment-grade long-term issuer credit rating by Fitch helps strengthen NOS's access to financing sources on favorable terms.

This information is also available on NOS's Investor Relations website in www.nos.pt/ir.

Lisbon, 26 july 2024

Contacts Maria João Carrapato Head of Investor Relations and Sustainability Email: ir@nos.pt Tel.: +351 21 782 4725 Fax: +351 21 782 4735