| Admin Alex Ltd | Thirsk | 2025 |
| Admin and Accounts Limited | Coventry | 2012 |
| Admin Army UK Limited | Brighton | 2020 |
| Admin Centre Ltd | Stroud | 2014 |
| Admin Consultancy Ltd | Mitcham | 2024 |
| Admin ELF Ltd | Grantown-On-Spey | 2020 |
| Admin Hub Ltd | Wakefield | 2019 |
| Admin Limited | Thatcham | 1994 |
| Admin Mater Ltd | London | 2015 |
| Admin Please Limited | London | 2024 |
| Admin Plus (Europe) Limited | Letchworth Garden City | 2004 |
| Admin R Ltd | London | 2024 |
| Admin Services (City) Limited | London | 1971 |
| Admin Services Avon Limited | Weston Super Mare | 1994 |
| Admin Site Services Ltd | Bramhall | 2025 |
| ADMIN4QS Limited | Holmfirth | 2007 |
| ADMIN4YOU Ltd | Kington | 2011 |
| Admincare Solutions Ltd | Witney | 2024 |
| Adminconsult Limited | Liverpool | 2023 |
| Admine Limited | Bexleyheath | 2023 |
| Administration & Accounting Services Limited | Tyne & Wear | 2003 |
| Administration Evaluation Services Ltd | Darlington | 2025 |
| Administration Gateway Limited | Blackburn | 2019 |
| Administrative Resources Limited | Knowle, Solihull | 2005 |
| Administrative Services Ltd. | Northampton | 2012 |
| Administrative Systems Limited | | 1983 |
| Administry Limited | London | 2026 |
| Adminize Ltd | London | 2024 |
| Adminpoint Limited | Bexley | 2001 |
| Adminquick Limited | Mirfield | 1986 |
| Adminrescue Limited | Cornwall | 2007 |
| Admint.Ai Limited | London | 2025 |
| Admio Capital Ltd | London | 2023 |
| Admira Partners UK Ltd | London | 2012 |
| Admirah Accountants Limited | Newcastle Upon Tyne | 2025 |
| Admiral Accounting Ltd | Feltham | 2011 |
| Admiral Design & Build Limited | Cowley, Oxford | 2016 |
| Admiral Developments Property Letting Limited | Ashford | 2013 |
| Admiral Hire Ltd | London | 2014 |
| Admiral Law Limited | Cardiff | 2012 |
| Admiral Maritime Limited | Petworth | 2018 |
| Admiral Public Relations and Marketing Limited | London | 1999 |
| Admiral Safety Limited | Mansfield | 2011 |
| Admiral Square Consultancy Ltd | Exeter | 2018 |
| Admiral Strategic Consulting Ltd | Feltham | 2024 |
| Admiral Taverns Bidco Limited | London | 2009 |
| Admiralty Finance Ltd | Reading | 2019 |
| Admiralty Holdings Limited | Taunton | 2002 |
| Admiralty Nominees Limited | London | 2024 |
| Admire and Rise Limited | London | 2025 |
| Admire Consultancy Ltd | London | 2025 |
| Admire Marketing Limited | Manchester | 2012 |
| Admitgo Ltd | London | 2025 |
| Admitt Ltd | Lisburn | 2025 |
| Admixer Limited | Watford | 2014 |
| Admmmxii Ltd | Banstead | 2012 |
| Admo Accountants Ltd | London | 2020 |
| Admo Financials Limited | St. Albans | 2012 |
| Admo Ltd | Ilford | 2010 |
| Admodigital Limited | Lancing | 2014 |
| Admodum London Limited | London | 2015 |
| Admonitum Limited | Cheltenham | 2011 |
| Admor Agency Ltd | Fishguard | 2023 |
| Admor Business Solutions Limited | Newtownabbey | 2007 |
| Admora Ltd | Beccles | 2025 |
| Admorphosis Ltd | Cardiff | 2025 |
| Admos AI Ltd | Mildenhall | 2025 |
| Admoss Company Limited | Thornton Heath | 2025 |
| Admotum Limited | Wallasey | 2013 |
| Admotus Marketing Limited | Coulsdon | 2009 |
| Admove Media Limited | Gloucester | 2022 |
| Admq Ltd | Stockport | 2023 |
| Admrs Services Ltd | London | 2019 |
| Adms Associates Limited | Birmingham | 2025 |
| Adms Limited | Londonderry | 2005 |
| Admx Ltd | Sittingbourne | 2024 |
| ADN Accounting Limited | London | 2020 |
| ADN Accounts & Book Keeping Services Limited | Newark | 2001 |
| ADN Business Solutions Ltd | London | 2015 |
| ADN Consultants Ltd | Leeds | 2011 |
| ADN Engineering Ltd | London | 2024 |
| ADN Holding Limited | London | 2019 |
| ADN Support & Development Limited | Barnsley | 2023 |
| Adnaan Ahmad Research Ltd | Cobham | 2016 |
| Adnaan Limited | Manchester | 2012 |
| Adnama Limited | Wellingborough | 2020 |
| Adnan & Aysha Arshad Limited | Edinburgh | 2018 |
| Adnan Accounting & Advisory Ltd | Rotherham | 2026 |
| Adnan ALI Advisory Ltd | Brentford | 2025 |
| Adnan Jahangir Limited | Southall | 2019 |
| Adnan Khadra Ltd | London | 2026 |
| Adnan Malik Limited | Manchester | 2018 |
| Adnan's Consultancy Ltd | Blackburn | 2015 |
| Adnanco Ltd | London | 2025 |
| Adnary Ltd | Clitheroe | 2017 |
| Adnation Media Ltd | Worcester | 2017 |
| Adnaw Accounting Services Ltd. | London | 2011 |
| Adndigital Limited | Huddersfield | 2016 |
| Adnet Marketing (Moto) Limited | London | 2023 |
| Adnet Marketing Limited | Glasgow | 2018 |