Marni Walden, who heads Verizon's sprawling media and digital operation is leaving the firm in February.
The 50-year-old, who is Verizon's highest-ranking woman executive, had been mentioned as a potential successor to CEO Lowell McAdam, 63.
“Marni helped build our wireless business, starting as a sales representative in a store and grew into an inspirational leader and role model for so many at Verizon,” McAdam said in a statement.
Walden was among executives who advocated on behalf of the $4.5B acquisition of Yahoo, according to the Wall Street Journal.
Yahoo has now disclosed that its hacking breach is more extensive than it had first thought, affecting 3B of its users.
Walden's duties will be divided among Verizon executives including former AOL CEO Tim Armstrong, who led the integration of Yahoo and AOL to form Oath.