Taking over the reigns will be Hans Vestberg, who joined the company just previous year as Executive Vice President and President of Global Networks and CTO at Verizon.
Vestberg, who served for six years as chief executive of Swedish wireless gear maker Ericsson, has been leading Verizon's push into next-generation, 5G wireless technology. Mr. McAdam will remain executive chairman until the end of the year and then become nonexecutive chairman.
Vestberg inherits a company that is losing its most valuable monthly subscribers and facing the threat of intensifying competition, as smaller, scrappier rivals Sprint and T-Mobile try once again to merge.
Vestberg will replace Lowell C. McAdam, who was named CEO in 2011.
"I strongly believe in the power of change to drive long-term growth and innovation", McAdam said in a company release announcing the news.
Hans Vestberg will be the next CEO at Verizon.
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Stratton, 57, has served Verizon and its predecessor, Bell Atlantic Mobile, for more than 25 years, holding various executive-level positions.
"The time for a change in leadership is now, and I am confident that Hans is the right person to bring Verizon through its next chapter", McAdam said, adding that "Hans is an energizing force" that will make Verizon a leader in "the emergence of technologies that blend the physical and the digital to create historic breakthroughs in connectivity and mobility".
"Effective immediately, Stratton will step down from his current role and will support a smooth transition as a strategic adviser reporting to Lowell McAdam", Verizon said in a statement Friday.
Under McAdam, Verizon took over the stake in the important wireless unit from Britain's Vodafone and built a customer base of more than 150 million.
Verizon said he led the acquisitions of major media, fiber and telematics assets, including AOL, Yahoo, XO Communications and optical fiber from Corning as well as divestment of wireline, tower and data center operations.
In fact, Hans Vestberg joined wireless operator Verizon after a one-year break after being fired in an investor-driven shakeup at Ericsson in 2016, following years of dismal growth and weak earnings.