| Armitage Pet Care Limited | Administrative & support | 2017 |
| Armitage Trustees Limited | Extraterritorial | 1999 |
| Armo Consulting Limited | Financial services | 2012 |
| Armoured Martial Arts Ltd | Manufacturing | 2023 |
| Arms of Ashton Limited | Information & communication | 2013 |
| Armstrong Aviation Clothing Limited | Wholesale & retail | 2007 |
| Armstrong Force Limited | Administrative & support | 2015 |
| Armstrong Security Limited | Administrative & support | 2023 |
| Armstrong Stokes & Clayton Limited | Construction | 2003 |
| Armstrong Supplies Limited | Wholesale & retail | 2015 |
| Armz Solutions Ltd | Construction | 2026 |
| Arnie Systems Limited | Information & communication | 2002 |
| Arno Enterprises Ltd | Transport & logistics | 2019 |
| Arnold & Carlton Veterinary Centre Limited | Professional & scientific | 2001 |
| Arnold & Central Electrical Services Limited | Wholesale & retail | 2003 |
| Arnold and District Liberal Club Company Limited(The) | Hospitality | 1888 |
| Arnold Building & Roofing Ltd | Construction | 2011 |
| Arnold Clutch & Gearbox Centre Ltd | Wholesale & retail | 2020 |
| Arnold Continental Supermarket Ltd | Wholesale & retail | 2023 |
| Arnold Dairies Limited | Wholesale & retail | 2006 |
| Arnold Dental Care Limited | Real estate | 2018 |
| Arnold Exchange Limited | Hospitality | 2018 |
| Arnold Hearing Specialist Limited | Wholesale & retail | 2019 |
| Arnold Home Care Ltd | Health & social care | 2025 |
| Arnold Lift Trucks Limited | Manufacturing | 2017 |
| Arnold Lodge Farm Limited | Agriculture & fishing | 2012 |
| Arnold PO Ltd | Wholesale & retail | 2025 |
| Arnold Point Ltd | Real estate | 2023 |
| Arnold Service Centre Ltd | Wholesale & retail | 2023 |
| Arnold Top Clean Ltd | Administrative & support | 2007 |
| Arnold Town Football Club Limited | Arts & recreation | 2005 |
| Arnold Traders Limited | Wholesale & retail | 2026 |
| Arnold TV Repairs Ltd | Other services | 2026 |
| Arnoldnotts Courier Services Limited | Transport & logistics | 2024 |
| Arnsa Limited | Hospitality | 2014 |
| Arnside Services Ltd | Other services | 2025 |
| Arockalypse Productions Ltd | Arts & recreation | 2018 |
| Aroi Aroi Ltd | Hospitality | 2025 |
| Aroma Desserts Limited | Hospitality | 2024 |
| Aromabella Limited | Real estate | 2024 |
| Aromatix PVT Ltd | Hospitality | 2025 |
| Aron & SID Transport Ltd | Wholesale & retail | 2017 |
| Aronaro Labs Ltd | Information & communication | 2026 |
| Arora Health Care Limited | Health & social care | 2018 |
| Arplace Ltd | Real estate | 2022 |
| ARR Ventures Ltd | Professional & scientific | 2025 |
| Arra Creatives Limited | Professional & scientific | 2025 |
| Arracol Limited | Construction | 2008 |
| Arrahba Limited | Health & social care | 2024 |
| Arran Court (Nottingham) Management Company Limited | Real estate | 1996 |
| Arran Jaiswal Consulting Limited | Professional & scientific | 2025 |
| Arrans Bagel (Notts) Limited | Hospitality | 2026 |
| Array PMO Services Limited | Professional & scientific | 2015 |
| Arrive Cars Ltd | Transport & logistics | 2019 |
| Arrow Building Services Limited | Construction | 2001 |
| Arrow Business Machines Limited | Manufacturing | 1989 |
| Arrow Ceilings Limited | Construction | 1991 |
| Arrow Delivery Ltd | Transport & logistics | 2016 |
| Arrow Estates Ltd | Construction | 2025 |
| Arrow Management Services (East Midlands) Limited | Real estate | 2003 |
| Arrow Music Limited | Manufacturing | 2025 |
| Arrow Orthodontics Limited | Health & social care | 2005 |
| Arrow Regulatory Limited | Professional & scientific | 2016 |
| Arrow Specialised Transport Limited | Other services | 2000 |
| Arrow Tech Solutions Ltd | Information & communication | 2022 |
| Arrowmist Limited | Information & communication | 2008 |
| Arrowsmith Transport Ltd | Transport & logistics | 2025 |
| Arry Properties Ltd | Real estate | 2022 |
| ARS Appliances Ltd | Wholesale & retail | 2019 |
| ARS Investment Solutions Ltd | Wholesale & retail | 2021 |
| ARS Tech Ltd | Information & communication | 2023 |
| Ars.Hmo Ltd | Real estate | 2026 |
| Arsheeyan Ltd | Health & social care | 2021 |
| Arshiya Ltd | Wholesale & retail | 2020 |
| Arslaan Barber Ltd | Other services | 2021 |
| Arsumon Limited | Professional & scientific | 2025 |
| Art 62 Limited | Professional & scientific | 2017 |
| Art Angel Studio Limited | Arts & recreation | 2012 |
| Art Audio (UK) Limited | Manufacturing | 1992 |
| Art by Lizzie Jayne (Nottingham) Limited | Arts & recreation | 2026 |
| Art Decorators Nationwide Limited | Construction | 1992 |
| Art Digital Limited | Professional & scientific | 2020 |
| Art Fest Limited | Arts & recreation | 2025 |
| Art Force Studios Ltd | Professional & scientific | 2017 |
| Art Forma (International) Limited | Manufacturing | 2013 |
| Art Forma Limited | Manufacturing | 2013 |
| Art Lettings Limited | Real estate | 2018 |
| Art of Football (Property) Ltd | Financial services | 2022 |
| Art of Football Ltd | Manufacturing | 2013 |
| Art Servicest Limited | Transport & logistics | 2015 |
| Art Sports PVT Ltd | Professional & scientific | 2025 |
| Art YOU Wear Ltd | Manufacturing | 2022 |
| Artaxis Holdings Ltd | Professional & scientific | 2023 |
| Artdocs Ltd | Information & communication | 2010 |
| Arten Digital Ltd | Financial services | 2024 |
| Arteo Consulting Limited | Professional & scientific | 2023 |
| Arteri Holdings Limited | Information & communication | 2001 |
| Arthaus Works Limited | Wholesale & retail | 2025 |
| Arthazen Traders Limited | Wholesale & retail | 2025 |
| Arthur Beck Construction Limited | Construction | 1976 |