Exhibit 99.1 FOR IMMEDIATE RELEASE Cogent Contacts: For Public Relations: For Investor Relations: Jocelyn Johnson John Chang + 1 (202) 295-4299 + 1 (202) 295-4212 jajohnson@cogentco.com investor.relations@cogentco.com Cogent Communications Reports First Quarter 2024 Results and Increases its Regular Quarterly Dividend on its Common Stock Financial and Business Highlights · Service revenue for Q1 2024 was $266.2 million and $272.1 million for Q4 2023. o Wavelength revenue increased sequentially by 7.0% to $3 ...