| 12 Dagnall Park Freehold Limited | London | 2026 |
| 12 Daniel Street Management Company Limited | Bath | 2018 |
| 12 Darlaston Road Residents Limited | London | 1981 |
| 12 Deacon Road (Freehold) Limited | London | 2017 |
| 12 Delamere Road Residents Association Limited | London | 1997 |
| 12 Dene Road RTM Company Limited | Guildford | 2021 |
| 12 Denmark Terrace (Brighton) Limited | Hove | 2012 |
| 12 Digby Crescent Limited | London | 2008 |
| 12 Donnington Bridge Road Ltd | Reading | 2025 |
| 12 Douglas Avenue Management Company Ltd | Seaford | 2022 |
| 12 Dulwich Road (Freehold) Limited | London | 2018 |
| 12 Durham Terrace Limited | London | 2000 |
| 12 Earls Court Square (Management) Limited | London | 1999 |
| 12 Eaton Road (Hove) Limited | Hove | 1996 |
| 12 Eccleston Square Limited | London | 1996 |
| 12 Edith Grove Residents Company Limited | London | 1999 |
| 12 Ellerker Gardens RTM Company Limited | Wadhurst | 2026 |
| 12 Elliston Road Management Company Limited | Bristol | 1985 |
| 12 Elmers END Road Management Company Ltd | London | 2019 |
| 12 Elton Mansions Management Company Limited | Bristol | 1991 |
| 12 Elton Road Management Company Limited | Clevedon | 1985 |
| 12 Esmond Road Freehold Limited | London | 2007 |
| 12 Esplanade Whitby Management Company Limited | Whitby | 2009 |
| 12 Essex Grove Limited | Epsom | 2013 |
| 12 Ethelbert Road RTM Company Limited | London | 2009 |
| 12 Eversfield Place Limited | Chelmsford | 2022 |
| 12 Eversfield Place ST Leonards on Sea RTM Company Limited | St. Leonards-On-Sea | 2004 |
| 12 Fairmount Road Limited | London | 2012 |
| 12 Farley Road Limited | Sittingbourne | 2023 |
| 12 Farquharson Road | Croydon | 2013 |
| 12 Fawcett Street Residents Limited | London | 1994 |
| 12 Fieldstile Road Limited | Norwich | 2021 |
| 12 Finborough Road Management Limited | Stockbridge | 1997 |
| 12 Fore Street Limited | Dartmouth | 1997 |
| 12 Fortess Road RTM Company Limited | London | 2015 |
| 12 Fourth Avenue Limited | East Sussex | 1998 |
| 12 Frant Road Management Limited | Marden | 1985 |
| 12 Frederick Place Clifton Bristol Management Company Limited(The) | Bristol | 1983 |
| 12 Freegrove Road Limited | | 1982 |
| 12 Fulwood Park (Liverpool) Management Limited | Bootle | 1983 |
| 12 Gascony Avenue (Management Company) Limited | London | 2022 |
| 12 Gayton Crescent NW3 Management Company Limited | | 1986 |
| 12 Geoffrey Road Residents Company Limited | London | 2002 |
| 12 Glebe Place Limited | | 1991 |
| 12 Gledhow Gardens Management Ltd | London | 2002 |
| 12 Glenhurst Road RTM Company Limited | Latchingdon | 2026 |
| 12 Grafton Square Management Company Limited | London | 2012 |
| 12 Graham Road Management Company Limited | London | 2018 |
| 12 Grassington Road (Eastbourne) Management Limited | Polegate | 2003 |
| 12 Green Lane Management Company Limited | Altrincham | 2004 |
| 12 Greencroft Gardens Limited | London | 1998 |
| 12 Greenwood Road Management Company Limited | | 1998 |
| 12 GRF Limited | Kingston Upon Thames | 2024 |
| 12 Griffiths Road RTM Company Limited | Harlow | 2016 |
| 12 Grosvenor Place (Bath) Management Company Limited | Bath | 1989 |
| 12 Guinea Lane (Bath) Limited | Avon | 1981 |
| 12 Hales Street RTM Company Limited | London | 2017 |
| 12 Hall Road Limited | Bromley | 1985 |
| 12 Hampshire Terrace RTM Company Limited | London | 2025 |
| 12 Hampton Park Management Company Limited | Bristol | 1979 |
| 12 Hampton Road, Bristol (Management) Limited | Bristol | 1982 |
| 12 Handforth Road Freehold Company Limited | London | 2021 |
| 12 Hangleton Road RTM Company Limited | Hove | 2025 |
| 12 Harrison Street (Residents) Limited | Hereford | 2007 |
| 12 Hazelmere Road Management Limited | | 1996 |
| 12 Healey Street Limited | London | 2010 |
| 12 Heathfield Road Tenants Limited | London | 2000 |
| 12 Henrietta Street (Bath) Management Company Limited | Bath | 1989 |
| 12 Henry Road Limited | | 1997 |
| 12 Henstead Road Management Company Limited | Eastleigh | 2018 |
| 12 Hertford Road Management Company Limited | London | 1997 |
| 12 Hewlett Road Limited | Cheltenham | 1996 |
| 12 Heyford Avenue Limited | | 2000 |
| 12 High Street Management & Maintenance Limited | Downend | 2012 |
| 12 High Street WUE Management Company Ltd | Wotton-Under-Edge | 2021 |
| 12 Hill Road Limited | Farnborough | 1971 |
| 12 Hillmarton Road N.7. Limited | St. Albans | 1970 |
| 12 Holmesdale Gardens (Hastings) Limited | St. Leonards-On-Sea | 2000 |
| 12 Hoscote Park Management Company Limited | Wirral | 2024 |
| 12 Hubbard Road (London) Limited | London | 2014 |
| 12 Hugh Street SW1 Freehold Limited | London | 2016 |
| 12 Hungerford Road Limited | | 1997 |
| 12 Iverson Road (Freehold) Limited | Edgware | 2022 |
| 12 Kelvin Grove Ltd | London | 2007 |
| 12 Kendal RD & 22 Wilson RD Management Company Limited | Lowestoft | 2006 |
| 12 Kendoa Road RTM Company Limited | London | 2012 |
| 12 Kensington Place Bath Limited | Bath | 2014 |
| 12 Kent House Road RTM Company Limited | London | 2025 |
| 12 King's Gardens Limited | Littlehampton | 1987 |
| 12 Kings Avenue Freehold Limited | London | 2024 |
| 12 Kingsley Road (Cotham) Management Company | Bristol | 1979 |
| 12 Kingsnorth Gardens (Management) Limited | Folkestone | 2006 |
| 12 Kingswood Road Management Limited | Hampton | 2005 |
| 12 KWW Limited | London | 2022 |
| 12 Lambert Road Limited | London | 1997 |
| 12 Langdale Terrace Management Company Limited | Whitby | 1991 |
| 12 Lansdowne Street Hove Limited | Hove | 2014 |
| 12 Leigham Court Road Limited | | 2003 |
| 12 Lennox Gardens Limited | London | 2006 |
| 12 Lexham Gardens RTM Company Limited | London | 2013 |