Optimus Telecomunictions, S.A. is a Portuguese GSM/UMTS mobile operator. The company was incorporated at the end of 1997 after winning the bid for Portugal's third GSM license. Optimus is a wholly owned subsidiary of Sonaecom (a sub-holding of Portuguese conglomerate Sonae, which is the major shareholder, with the France Telecom holding company Atlas Services Belgium (ASB) as the largest minority owner).

Optimus, initially under the Clix brand, was a pioneer of IPTV, launching in 2003 and constantly innovating since. They have successfully navigated many of the pitfalls that await IPTV operators and are now expanding their services across an ambitious FTTH rollout as well. In March 2010 VO’s content discovery solution, COMPASS, was added to the service.