Private company

O2

Logo: Telefónica Germany GmbH & Co. OHG, Public domain, via Wikimedia Commons3

British telecommunications provider

Telefonica UK Limited, trading as O2 UK (stylised as O2), is a British telecommunications services provider. It is the second largest mobile network in the United Kingdom behind VodafoneThree, with approximately 22.4 million subscribers as of December 2025.2 It is part of Virgin Media O2.1 Wikipedia text CC BY-SA 4.0

Last updated Oct 20, 2026.

Overview

1985Founded1
  • Industrymobile phone industry, telecommunications industry1
  • HeadquartersSlough1
  • Websiteo2.co.uk

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Telefonica UK Limited, trading as O2 UK (stylised as O2), is a British telecommunications services provider. It is the second largest mobile network in the United Kingdom behind VodafoneThree, with approximately 22.4 million subscribers as of December 2025.2

Corporate structure

O2 is part of a group headed by Telefónica. 85 entities, 15 countries on record. Switch between the flow chart and the network, and select any entity to see its details.

Built from parent and subsidiary links from GLEIF, the Global Legal Entity Identifier Foundation (CC0); subsidiaries, stakes and holdings from Wikidata (CC0). Each entity in the chart links to its source.

Subsidiaries and ownership

Parent company

Owners

Former owners and parents

From Wikidata.1

Timeline

  1. Jun 1, 2021Acquired Acquired by Virgin Media O21
  2. Nov 30, 2005Acquired Acquired by Telefónica1
  3. 1985Founded Founded1

Sources

The numbers on this page point here. Each one links to the record it came from.

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