CSL Mobile Limited, a telecommunications company based in Hong Kong, was the region's first mobile communications operator established in 1983. The company operates mobile network brands such as "csl", "1O1O" and "Club SIM". CSL was initially a subsidiary of Hong Kong Telecom (HKT) and was the first network to launch the world’s first dual band 4G LTE network with DC-HSPA+. Throughout its history, the brand CSL has been under various legal entities, namely Communication Services Limited, known as Hong Kong Telecom CSL Limited from 1990 to 1999, Cable & Wireless HKT CSL Limited from 1999 to 2001, and Hong Kong CSL Limited from 2001. The current legal entity of the brand, CSL Mobile Limited, was formerly known as PCCW Mobile HK Limited, a result of the merger of the brands CSL and PCCW Mobile. In the 1990s, CSL was a part of PCCW (formerly HKT). In 2002, PCCW sold CSL, but re-entered the mobile network operator business in 2005 by acquiring SUNDAY and setting up a new brand "PCCW Mobile". In 2014, HKT, a member of the PCCW Group, acquired CSL New World Mobility and its subsidiaries such as CSL Limited and New World Mobility. The legal entity of PCCW Mobile was renamed to CSL Mobile Limited in 2014, and has since used the brand CSL. The abbreviation CSL was originally for Communication Services Limited and their branding of "Create a Simple Life". The CSL brand, logo and corporate colour (green) were all updated in August 2011 and again in recent years.
Alias
Hong Kong Telecommunications (HKT) Limited
Country
Type
Network Operator
CSL HK logo

3G Network

The company launched 3G UMTS over B1 (2100 MHz) in September 2006. CSL's 3G network was upgraded to HSPA+ in March 2009, and B8 (900 MHz) added late the same year. DC-HSPA+ was implemented October 2011.

    Network Frequency Band Status
    Active
    Date Event Subtype
    Launch of 3G Network
    Launch

    4G Network

    CSL's 4G LTE network operates over Genius Brand's infrastructure, which went live May 2011 (after pre-release to corporate customers November 11). The network, shared with 3 Hutchison, operates over B3 (1800 MHz) and B7 (2600 MHz), originally with 2x15 MHz channel widths which were later expanded to 2x20 MHz. LTE-A was implemented October 2013 which provided 2C CA_3A-7A.

    The network was upgraded again in May 2017 to support LTE-A Pro, with 3C CA_3A-7A-7A (B3+B7+B7), and 256QAM technologies, achieving peak data rates of 600 Mbps.

      4G Frequency Bands
      Network Frequency Band Max. Channel Bandwidth Status
      20
      Active
      20
      Active
      20
      Active
      Date Event Subtype
      Launch of 4G network
      Launch

      5G Network

      The company launched its 5G network in April 2020 using n78 and n79 mid-band.

        Network Frequency Band Max. Channel Bandwidth Status
        10
        Active
        80
        Active
        40
        Active
        400
        Active
        Date Event Subtype
        Launch of 5G network
        Launch