| Advent Consult Ltd | Enfield | 2018 |
| Advent Consulting Solutions Limited | Chelmsford | 2019 |
| Advent Data Solutions Ltd | Stanmore | 2009 |
| Advent IM Limited | Halesowen | 2002 |
| Advent Insurance Management Limited | Chelmsford | 2015 |
| Advent Media Ltd | London | 2025 |
| Adventa Consulting Ltd | Wakefield | 2023 |
| Adventec Limited | Wakefield | 2025 |
| Adventfs, Ltd | Brighton | 2024 |
| Adventia Ltd | Rickmansworth | 2014 |
| Adventico Ltd | Milton Keynes | 2020 |
| Adventics Ltd | Wakefield | 2020 |
| Adventine Ltd | Ipswich | 2025 |
| Adventis Digital Limited | Glasgow | 2024 |
| Adventist Radio London | Watford | 2017 |
| Adventix Limited | London | 2017 |
| Adventor Ltd | Woking | 2022 |
| Adventori London Ltd | London | 2016 |
| Adventoris Ltd | Huddersfield | 2012 |
| Adventrio Ltd | Littlehampton | 2023 |
| Adventura Semper Limited | London | 2026 |
| Adventura Studios Ltd. | Crieff | 2025 |
| Adventure Alliance Films Ltd | Newcastle Upon Tyne | 2022 |
| Adventure Camp Limited | Fareham | 2015 |
| Adventure Clues Ltd | Manchester | 2023 |
| Adventure DAD Ltd | Colden Common | 2024 |
| Adventure Emporium Ltd | Sheffield | 2026 |
| Adventure Entertainment UK Ltd | London | 2019 |
| Adventure Everything Ltd | Edinburgh | 2019 |
| Adventure Growth Company Ltd | London | 2025 |
| Adventure Growth Partners Ltd | Bourne | 2025 |
| Adventure Illustrated Ltd | London | 2018 |
| Adventure Integrated Services Ltd | Kings Langley | 2025 |
| Adventure IP Ltd | Rossendale | 2025 |
| Adventure MAP Ltd | Paisley | 2022 |
| Adventure Medic Ltd | Glasgow | 2013 |
| Adventure N Snack UK Limited | London | 2023 |
| Adventure of Humanity Ltd | London | 2016 |
| Adventure Pictures (Orlando) Limited | London | 1992 |
| Adventure Pictures (Rage) Limited | London | 2008 |
| Adventure Pictures (YES) Limited | | 2003 |
| Adventure Pictures Limited | London | 1989 |
| Adventure Radio Limited | Leigh-On-Sea | 2005 |
| Adventure Records Limited | Henley-On-Thames | 2002 |
| Adventure Screen Limited | Holburn | 2024 |
| Adventure Show Productions Limited | Newtonmore | 2015 |
| Adventure Skills Online Ltd | Llanfairfechan | 2020 |
| Adventure Soft Publishing Limited | Sutton Coldfield | 1998 |
| Adventure Sports Media House Ltd | Dursley | 2020 |
| Adventure Sports Media Ltd | Poole | 2019 |
| Adventure Sprout Ltd | Dundee | 2025 |
| Adventure Technologies Ltd | Oxford | 2025 |
| Adventure Telecom Ltd | Salford | 2017 |
| Adventure Television Limited | Maidenhead | 2008 |
| Adventure With Easha Ltd | Potters Bar | 2023 |
| Adventureman Ltd | Quedgeley | 2014 |
| Adventureready Ltd | Halesowen | 2025 |
| Adventures & Experiences Ltd | Glossop | 2022 |
| Adventures by Mail (Europe) Limited | Stockport | 1995 |
| Adventures Down Memory Lane Limited | Warrington | 2019 |
| Adventures in Business Ltd | Kidderminster | 2018 |
| Adventures in Freelance Limited | Blackburn | 2023 |
| Adventures in Honeywood Ltd | Swansea | 2023 |
| Adventures in Marketing Ltd | London | 2025 |
| Adventures in Sound Ltd | Wincanton | 2013 |
| Adventures of the Wests Limited | Crowborough | 2026 |
| Adventures.Ai Ltd. | London | 2024 |
| Adventurex Limited | Leeds | 2005 |
| Adventuron Software Limited | Stockton-On-Tees | 2019 |
| Adventurous Audio Ltd | Ullapool | 2020 |
| Adventurous Systems Ltd | London | 2023 |
| Adventury XR Limited | Lancing | 2024 |
| Advenue Limited | Kington | 2017 |
| Adveo Limited | London | 2026 |
| Advera Limited | London | 2013 |
| Adverbuzz Ltd | Watford | 2025 |
| Adverity Technologies Ltd | London | 2018 |
| Adverly Solutions Ltd | Birmingham | 2024 |
| Advermercial Limited | Felixstowe | 2020 |
| Adversarial Engineering Ltd | London | 2025 |
| Adversarial Security Ltd | London | 2025 |
| Adversify Ltd | York | 2022 |
| Adversity Games Ltd. | Sunderland | 2016 |
| Adversity Songs Ltd | Liverpool | 2022 |
| Advert Area Limited | Brighton | 2014 |
| Advert Clock Ltd | Blackburn | 2025 |
| Advert Here Ltd | London | 2016 |
| Advert Leap Ltd | London | 2021 |
| Advert Optimizer Limited | Prenton | 2011 |
| Advertainment Media Limited | Tunbridge Wells | 2014 |
| Advertasio Limited | London | 2025 |
| Advertax Ltd | London | 2025 |
| Advertaz Ltd | Sheffield | 2026 |
| Adverte Media Group Ltd | York | 2026 |
| Adverti Digital Limited | Witney | 2021 |
| Adverti Ltd | Birmingham | 2026 |
| Adverti Tech Global Ltd | London | 2023 |
| Advertico Limited | Birmingham | 2013 |
| Advertise Limited | Newbury | 1991 |
| Advertisement Strike Ltd | London | 2022 |