One.Vip

One.Vip was created by the 2015 merger of One, owned by Telekom Slovenije (which had acquired it from OTE), and Vip operator, owned by A1 Telekom Austria Group, which owns the entirety of the company (up from 55%) after Telekom Slovenije agreed to give up its 45% stake.

2009–2015
In 2009, OTE sold Cosmofon to Telekom Slovenije, which renamed it to One.