COGENT COMMUNICATIONS HOLDINGS, INC.

Code of Conduct and Ethics

(adopted October 21, 2003, amended September 12, 2006 and April 28, 2021)

The Board of Directors of Cogent Communications Holdings, Inc. (the “Company”) promulgates this Code of Ethics governing the conduct and responsibilities of the directors, officers and employees of the Company and its subsidiaries. All such individuals shall:

1)act with honesty and integrity and shall use due care and diligence in performing their responsibilities to the Company.

2) avoid situations that represent actual or apparent conflicts of interest with their responsibilities to the Company and shall promptly disclose to the Chief Legal Officer or the chairman of the Audit Committee any transaction or personal or professional relationship that reasonably could be expected to give rise to such an actual or apparent conflict.

3) provide the board of directors, auditors, regulatory agencies and others, as necessary, with information that is accurate, complete, fair, relevant, timely and understandable, including information for inclusion in the Company’s public statements or in submissions to governmental agencies.

4) comply with applicable laws, rules and regulations, the rules of any applicable public or private regulatory and listing authorities and the policies and procedures established by the Company.

5) refrain in all cases from soliciting, receiving or giving gifts, bribes, facilitation payments or other similar remuneration or consideration whether directly for oneself or for a family member.

6) respect and safeguard the confidentiality of information acquired in the course of their work except as authorized or legally obligated to disclose such information. Confidential information acquired in the course of an individual’s work for the Company shall not be used for personal advantage.

7) share knowledge and maintain skills important and relevant to the Company’s needs.

8) promote high integrity in the work environment.

9) maintain control over and use for the benefit of the Company all Company assets and resources entrusted to them.

Any violations of this code should be reported to the Chief Legal Officer or a member of the Audit Committee.  Reports may be made anonymously as described in the Company’s whistleblower policy.  Individuals reporting violations will be protected from retaliation for reporting a violation pursuant to that policy (though an individual who has violated this code may be punished).