| 12 Shipgate Street Limited | Chester | 2017 |
| 12 Sinclair Gardens Management Company Limited | Southampton | 2000 |
| 12 Skerne Road (Kingston) Management Company Limited | Bromley | 2010 |
| 12 Sloane Gardens Freehold Limited | London | 2024 |
| 12 South Terrace Property Management Limited | Hove | 2001 |
| 12 Southend Road Management Company Limited | Beckenham | 1995 |
| 12 Southfield Road Management Company Limited | Bristol | 1998 |
| 12 Spencer Hill (Wimbledon) Limited | London | 1987 |
| 12 Springfield Court (Stonehouse) Management Company Limited | Stonehouse | 2024 |
| 12 Springfield Road (Brighton) Limited | Brighton | 2019 |
| 12 Springfield Road Limited | Crawley | 2015 |
| 12 ST Andrews Road Portslade Limited | Brighton | 2008 |
| 12 ST Catherine Street (Gloucester) Limited | Gloucester | 2002 |
| 12 ST Gabriels Road Limited | London | 1992 |
| 12 ST Georges Terrace RTM Company Limited | Brighton | 2011 |
| 12 ST Johns Road (Watford) Limited | Watford | 2024 |
| 12 ST Lukes Road Freehold Limited | Berkshire | 2005 |
| 12 ST Mark's Place (2) Limited | London | 2001 |
| 12 ST Martins Lane RTM Company Limited | Edenbridge | 2014 |
| 12 ST Martins Square Maintenance Ltd | Scarborough | 2022 |
| 12 ST Mary Street Management Company Limited | Bridgwater | 2008 |
| 12 Stafford Terrace Freehold Ltd | London | 2021 |
| 12 Stanhope Place Management Company Limited | Salisbury | 2002 |
| 12 Station Road Management Limited | Bristol | 2008 |
| 12 Stillhouse Lane RTM Company Ltd | Weston-Super-Mare | 2024 |
| 12 Stockleigh Road Freehold Company Limited | Hastings | 2021 |
| 12 Strathmore Gardens Limited | London | 1996 |
| 12 Summerlays Place (Bath) Management Company Limited | Bristol | 1983 |
| 12 Swains Lane Limited | | 2004 |
| 12 Tanza Road Management Company Limited | London | 1983 |
| 12 Teignmouth Road RTM Company Limited | London | 2026 |
| 12 the Barons RTM Company Limited | Wokingham | 2024 |
| 12 the Circus Management Company Limited | Bristol | 2019 |
| 12 the Down RMC Limited | Bristol | 2018 |
| 12 the Mall Management Co. Limited | Bristol | 1984 |
| 12 the Parade Swanage Limited | Swanage | 2000 |
| 12 Thornhill Road (Plymouth) Management Limited | Plymouth | 2017 |
| 12 Thurloe Place Limited | Bromley | 1995 |
| 12 to 15 Saville Place (Clifton) Limited | London | 2020 |
| 12 Tournay Road Freehold Limited | London | 2020 |
| 12 Tredegar Square Residents Company Limited | | 2002 |
| 12 Tremadoc Road Limited | | 1997 |
| 12 Treport Street (Wandsworth) Management Company Limited | Croydon | 1989 |
| 12 Turle Road Ltd | | 2001 |
| 12 Tysoe Management Limited | London | 2007 |
| 12 Ullswater Road Limited | London | 2003 |
| 12 Ulverscroft Road Ltd | London | 2025 |
| 12 Upper Lewes RTM Company Limited | Wadhurst | 2025 |
| 12 Upper Maudlin Street Management Company Limited | Bristol | 2014 |
| 12 Verbena Gardens W6 9TP Limited | London | 2006 |
| 12 Victoria Avenue Management Limited | Manchester | 2010 |
| 12 Victoria Road North Limited | Hampshire | 2007 |
| 12 Victoria Square Management Company Limited | Bristol | 1990 |
| 12 Vyvyan Terrace Management Limited | Bristol | 1979 |
| 12 Walpole Street Freehold Limited | Croydon | 2016 |
| 12 Walpole Terrace (Brighton) Limited | East Sussex | 2005 |
| 12 Walton`S Parade Management Company Limited | Lytham St Annes | 2007 |
| 12 Wandsworth Common Northside Management Company Limited | London | 2009 |
| 12 Warrington Crescent Freehold Limited | London | 2018 |
| 12 Waverley Road Management Co. Limited | Hayling Island | 2005 |
| 12 Wellesley Villas Management Limited | Ashford | 1996 |
| 12 West Mall Management Limited | Bristol | 1980 |
| 12 West Shrubbery Management Limited | Weston-Super-Mare | 2020 |
| 12 West Street Management Limited | Weston-Super-Mare | 2013 |
| 12 West Terrace RTM Company Limited | Eastbourne | 2022 |
| 12 Westbourne Terrace Road Limited | London | 2026 |
| 12 Whittingstall Road RTM Company Limited | London | 2023 |
| 12 Whorlton Road Limited | London | 2020 |
| 12 Widcombe Crescent (Bath) Limited | Avon | 1988 |
| 12 Wilbury Road (Hove) Limited | Hove | 2013 |
| 12 Wilderness Road Management Limited | Plymouth | 1995 |
| 12 Woodstock Road East (Begbroke) Management Company Limited | Banbury | 2013 |
| 12 Woolstone Road Management Company Limited | London | 2005 |
| 12 Wyndham Square Company Limited | Plymouth | 2016 |
| 12 York Place Limited | Bristol | 1992 |
| 12, Bellevue (Clifton) Management Company Limited | Bristol | 1980 |
| 12, Brock Street, Bath Limited | Bath | 1986 |
| 12, Cambridge Park Management Company Limited | Twickenham | 1982 |
| 12, Victoria Walk Cotham Bristol Limited | Bristol 6 | 1986 |
| 12,AVENUE Crescent Limited | | 1990 |
| 12-12A Easton Road Management Limited | Witham | 2020 |
| 12-12A Maple Road Ltd | London | 2024 |
| 12-13 Richmond Buildings RTM Company Limited | London | 2019 |
| 12-14 ALL Saints RD Freeholders Limited | Sutton | 2013 |
| 12-14 Bradford Road RTM Company Ltd | Pudsey | 2024 |
| 12-14 Carriage Mews Limited | Ashford | 2001 |
| 12-14 Cleveland Square Freehold Limited | Watford | 2016 |
| 12-14 Clifton Gardens (Management) Limited | London | 1987 |
| 12-14 Crossbeck Road RTM Company Limited | Ilkley | 2010 |
| 12-14 Egerton Place Freehold Limited | London | 2007 |
| 12-14 New North Street RTM Company Limited | Harlow | 2011 |
| 12-14 Parkgate Limited | Haslemere | 2019 |
| 12-14 Warrior Square RTM Company Limited | London | 2025 |
| 12-16 Ainsley Street Limited | London | 2023 |
| 12-16 ELM Road Management Limited | Leatherhead | 2017 |
| 12-16 Strathearn Drive RTM Company Limited | Bristol | 2021 |
| 12-18 Deck Close (London) RTM Company Limited | Bromley | 2024 |
| 12-18 Gabalfa Road Management Company Limited | Swansea | 1990 |
| 12-18 Greenock Mews RTM Company Limited | Widnes | 2020 |
| 12-18 High Road Management Company Limited | London | 2022 |