Investor Presentation

First Quarter 2022

"ATN is focused on building a strong communications network and subscriber base in traditionally under-built or under-served market segments.

This delivers high recurring revenues, durable cash flows, reliable dividends, and long-term shareholder value."

Michael Prior, CEO

ATNI: Nasdaq

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Forward-Looking Statements & Non-GAAP Financial Information

This presentation may contain forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended. All statements other than statements of historical fact are or may be forward-looking statements. Forward-looking statements can generally be identified by the use of words that include phrases such as "believe," "expect," "anticipate," "plan," "foresee," "likely," "will," or other similar words and phrases. Actual future events and results could differ materially from the events and results indicated in these statements as a result of many factors, including, those set forth in Item 1A "Risk Factors" of ATN's Annual Report on Form 10K for the year ended December 31, 2021, which is on file with the SEC, and our other public reports. ATN undertakes no obligation to update these forward-looking statements to reflect actual results, changes in assumptions or changes in other factors that may affect such forward-looking statements.

This presentation includes certain non-GAAP financial measures. The most directly comparable GAAP measures and reconciliations to those GAAP measures are provided at the end of this presentation.

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"ATN is in the midst of its next growth phase. We are rapidly deploying fiber and fiber-fed high-speed data solutions to more homes, businesses, schools, and communities, as well as to other communications providers. Consistent with our market strategy, we continue to invest in historically underserved and remote markets that are often overlooked by larger players."

Michael Prior, CEO

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Connectivity: Life-Changing Importance for Communities; Lasting Opportunity for ATN

"We are located in the remote Yukon Delta region

of Alaska. The region has high poverty, and the only reliable internet connections are to the school and the health clinic. It is very hard to conduct 'remote learning' when none of the students have Internet connections."

Yukon Delta, Alaska

Northeast Arctic School Board, Alaska

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