| Arlington NO.3 Bond Issuer PLC | London | 2016 |
| Arlington ROW Wealth Management Ltd | Bristol | 2024 |
| Arlington Westcountry Debtco PLC | London | 2019 |
| Arlo Capital Ltd | Weybridge | 2025 |
| Arlo Chester Enterprise Ltd | Hartlepool | 2021 |
| Arlo Equity Ltd | London | 2025 |
| Arlo Hawk Limited | Yeovil | 2021 |
| Arlo Risk Assessment Ltd | London | 2024 |
| Arlo SW Holdings Limited | Newton Abbot | 2024 |
| Arlo Trading Ltd | London | 2026 |
| ARM Around Care Group Limited | Manchester | 2023 |
| ARM Asia Investment G.P. Limited | Cambridge | 2016 |
| ARM DEV Energy Ltd | London | 2023 |
| ARM Finance Overseas Limited | | 2005 |
| ARM Financial Services UK Ltd | London | 2024 |
| ARM Holdings PLC | Cambridge | 2018 |
| ARM Secure Holdings Limited | Warrington | 2015 |
| ARM Technology Investments 2 Limited | Cambridge | 2019 |
| ARM Technology Investments Limited | Cambridge | 2014 |
| ARM UK Holdings Limited | | 2005 |
| Arma Europe Limited | Colchester | 2015 |
| Arma Fusion Ltd | London | 2016 |
| Arma Holdings Limited | Leicester | 2024 |
| Arma Investments Limited | Edgware | 2022 |
| Arma Karma Limited | Colchester | 2019 |
| Armaan Holdings Ltd | Blackburn | 2020 |
| Armac Capital Ltd | Beaminster | 2015 |
| Armac Services Limited | Biggar | 2021 |
| Armacana Limited | London | 2024 |
| Armacell Insulation UK Holding Limited | Oldham | 2012 |
| Armacell United Kingdom Holding Limited | Oldham | 2000 |
| Armada Bidco Limited | Gloucester | 2020 |
| Armada Cider Ltd | Rochdale | 2020 |
| Armada Corporate Contracts Limited | Wolverhampton | 2016 |
| Armada Credit Group Ltd | London | 2022 |
| Armada Investments Limited | Exeter | 1973 |
| Armada Midco Limited | Gloucester | 2020 |
| Armada Topco Limited | Gloucester | 2020 |
| Armadale Capital PLC | London | 2005 |
| Armadillo Associates Holdings Limited | Bristol | 2017 |
| Armadillopay (UK) Limited | Belfast | 2023 |
| Armadillopay Limited | London | 2022 |
| Armagard Holdings Ltd | Birmingham | 2021 |
| Armagh Tavern Newco Ltd | Newry | 2025 |
| Armagold Limited | 3 Dorset Rise | 2000 |
| Arman Exchange Ltd | Hayes | 2020 |
| Armand Networks Ltd | Consett | 2016 |
| Armani & Associates Ltd | London | 2025 |
| Armatile Holdings Limited | Armagh | 2023 |
| Armazia Group Limited | London | 2026 |
| Armchair Adviser Ltd | Cannock | 2024 |
| Armchair Mortgages Limited | Cannock | 2001 |
| Armco Asset Management Limited | Orpington | 2022 |
| Armco Direct (Holdings) Ltd | Loughborough | 2016 |
| Armcon EOT Limited | Poynton | 2020 |
| Armcul Investments Ltd | Lisburn | 2026 |
| Arme Holdings Limited | Ashbourne | 2024 |
| Armed & Advised Limited | Solihull | 2014 |
| Armeg EOT Limited | Dronfield | 2024 |
| Armen Partners UK Limited | London | 2022 |
| Armengou Holding Ltd | Kington | 2022 |
| Armentum Holdings Ltd | Stone | 2026 |
| Armetor Holdings Ltd | Edinburgh | 2026 |
| Armeus Ltd | Liverpool | 2025 |
| Armex Investments Limited | Barnstaple | 2026 |
| Armfield Financial Ltd | Norwich | 2019 |
| Armiger International Limited | London | 2023 |
| Armik Capital Ltd | London | 2025 |
| Armila Capital Limited | London | 2012 |
| Armill Holdings Limited | Braintree | 2025 |
| Armillary Bidco Limited | London | 2023 |
| Armillary Midco 1 Limited | London | 2023 |
| Armillary Midco 2 Limited | London | 2023 |
| Armillary Topco Limited | London | 2023 |
| Armin Holdings Limited | Southend-On-Sea | 2024 |
| Armina Holdings Ltd | Enfield | 2024 |
| Armira Capital Limited | London | 2015 |
| Armira UK Limited | London | 2025 |
| Armishaws Group Limited | Gillingham | 2020 |
| Armishaws Media Limited | Gillingham | 2022 |
| Armison Corporation Ltd | Leicester | 2026 |
| Armitage BT Limited | Chorley | 2023 |
| Armitage Capital Ltd | London | 2017 |
| Armitage Financial Advisers Limited | Lancashire | 2005 |
| Armitage Financial Solutions Limited | Leeds | 2013 |
| Armitage Industrial 4 Limited | London | 2023 |
| Armitage Industrial Holdings Limited | London | 2023 |
| Armitage Industrial Reitco Limited | London | 2023 |
| Armitage Legacy Group Ltd | Liverpool | 2026 |
| Armitstead Barnett Financial Services Limited | Preston | 2002 |
| Armlee Group Limited | Chorley | 2021 |
| Armo Consulting Limited | Nottingham | 2012 |
| Armoni Holdings Ltd | London | 2024 |
| Armor Property Protection Ltd. | London | 2021 |
| Armored Holdings Ltd | Peterborough | 2022 |
| Armorgard Group Holdings Limited | Fareham | 2024 |
| Armorgard Holdings Limited | Fareham | 2017 |
| Armorica Investment Limited | London | 2011 |
| Armorica Ltd | London | 2019 |
| Armorica Services Limited | London | 2017 |