| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| Bt Cellnet Ltd | 04196992 | 29/11/2001 | Dissolved |
| CALL CONNECTIONS LIMITED | 02712995 | 10/11/2009 | Dissolved |
| CELLPHONES DIRECT (INVESTMENTS) LIMITED | 03066790 | 10/11/2009 | Dissolved |
| CELLPHONES DIRECT LIMITED | 02995222 | 10/11/2009 | Dissolved |
| Celldata Ltd | 01906153 | 19/11/2001 | Dissolved |
| Cellphones Direct (Holdings) Ltd | 03065866 | 10/11/2009 | Dissolved |
| Cellroute Limited | 01906154 | 19/11/2001 | Dissolved |
| Cellstore Limited | 01906155 | 19/11/2001 | Dissolved |
| Cellwest Ltd | 01824149 | 19/11/2001 | Dissolved |
| DX COMMUNICATIONS (EDINBURGH) LIMITED | SC144905 | 10/11/2009 | Dissolved |
| GENIE INTERNET LIMITED | 04330446 | 10/11/2009 | Dissolved |
| LINK FS LIMITED | 03357545 | 10/11/2009 | Dissolved |
| LUMINA HOLDINGS LIMITED | 02667014 | 10/11/2009 | Dissolved |
| MMO2 Holdings Ltd | 04273336 | 20/05/2002 | Dissolved |
| MMO2 International Ltd | 04278129 | 20/05/2002 | Dissolved |
| O2 (Germany) Verwaltungs Gmbh | FC020858 | 19/11/2001 | Dissolved |
| O2 (ONLINE) LIMITED | 01906156 | 10/11/2009 | Dissolved |
| O2 CREDIT VOUCHERS LIMITED | 04273243 | 10/11/2009 | Dissolved |
| O2 LIMITED | 04330445 | 10/11/2009 | Dissolved |
| O2 MOBILES LIMITED | 02604355 | 10/11/2009 | Dissolved |
| O2 SOLUTIONS LIMITED | 01814089 | 10/11/2009 | Dissolved |
| O2 THIRD GENERATION | 03900219 | 10/11/2009 | Dissolved |
| O2 TRANSACTIONS LIMITED | 02713001 | 10/11/2009 | Dissolved |
| OXY2 Communications Ltd | 04251212 | 20/05/2002 | Dissolved |
| OXY2 Ltd | 04251198 | 20/05/2002 | Dissolved |
| Oxy Communications Ltd | 04251219 | 20/05/2002 | Dissolved |
| Oxytel Ltd | 04254093 | 20/05/2002 | Dissolved |
| PACIFIC SHELF 873 LIMITED | SC198346 | 10/11/2009 | Dissolved |
| TELEFONICA FINANCIAL SERVICES UK LIMITED | 07584114 | 23/07/2014 | Dissolved |
| TELEFONICA GLOBAL RESOURCES LIMITED | 02664011 | 10/11/2009 | Dissolved |
| Telecom Securicor Cellular Radio Ltd | 01906157 | 19/11/2001 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| AIRWAVE SOLUTIONS LIMITED | 03985643 | 19/11/2001 | 20/04/2007 | One Red Flag |
| AXONIX LTD | 08953245 | 11/04/2014 | 03/08/2018 | Strike Off |
| CORNERSTONE TELECOMMUNICATIONS INFRASTRUCTURE LIMITED | 08087551 | 18/10/2013 | 27/03/2015 | Bronze |
| MMO2 LIMITED | 04190833 | 07/07/2016 | 17/06/2021 | Not Trading |
| O2 (EUROPE) LIMITED | 04247143 | 10/11/2009 | 17/06/2021 | Silver |
| O2 (UK) LIMITED | 02012647 | 10/11/2009 | 18/06/2021 | Not Trading |
| O2 INTERNATIONAL HOLDINGS LIMITED | 04247157 | 10/11/2009 | 17/06/2021 | Dissolved |
| O2 NETWORKS LIMITED | 02604351 | 10/11/2009 | 01/10/2012 | Gold |
| O2 OAK LIMITED | 03646040 | 10/11/2009 | 17/06/2021 | Not Trading |
| O2 PINE LIMITED | 06281240 | 10/11/2009 | 18/06/2021 | Not Trading |
| O2 WILLOW LIMITED | 06281241 | 10/11/2009 | 18/06/2021 | Not Trading |
| O2 WORLDWIDE LIMITED | 09690368 | 16/07/2015 | 18/06/2021 | Bronze |
| SKY HOME COMMUNICATIONS LIMITED | 05262862 | 10/11/2009 | 30/04/2013 | Not Trading |
| TELEFONICA DIGITAL LIMITED | 07884976 | 16/12/2011 | 18/06/2021 | Amber |
| TELEFONICA FINANCIAL SERVICES UK LIMITED | 07584114 | 30/03/2011 | 02/11/2011 | Dissolved |
| TELEFONICA GERMANY HOLDINGS LIMITED | 08202391 | 05/09/2012 | 17/06/2021 | Bronze |
| TELEFONICA O2 HOLDINGS LIMITED | 05310128 | 27/03/2020 | 17/06/2021 | Silver |
| TELEFONICA O2 UK LIMITED | 04330394 | 10/11/2009 | 18/06/2021 | Not Trading |
| TELEFONICA UK HOLDINGS LIMITED | 03722259 | 19/11/2001 | 10/11/2009 | Not Trading |
| THE LINK STORES LIMITED | 03317483 | 15/09/2006 | 18/06/2021 | Not Trading |
| WAYRA SOCIAL VENTURES LIMITED | 08520105 | 04/01/2016 | 18/06/2021 | Dissolved |
| WAYRA UK LIMITED | 08083534 | 25/05/2012 | 18/06/2021 | Bronze |