| Autotaps Limited | Manufacturing | 2008 |
| Autown Hire Ltd | Administrative & support | 2022 |
| Autumn Summer Ltd | Administrative & support | 2025 |
| AV Accountancy & Tax Services Ltd | Professional & scientific | 2025 |
| AV Fruit & VEG Ltd | Wholesale & retail | 2025 |
| AV London(Uk) Ltd | Other services | 2024 |
| AV Pharmacare Ltd | Professional & scientific | 2024 |
| Av-It UK Systems Limited | Construction | 2018 |
| AVA Ruby Properties Ltd | Real estate | 2022 |
| Avalon (Bath) Management Limited | Households | 1999 |
| Avamont Site Services Limited | Construction | 2010 |
| Avan Properties Ltd | Real estate | 2019 |
| Avancee Limited | Real estate | 2021 |
| Avant Garde Consultants PVT Ltd | Real estate | 2010 |
| Avant-Garde Wisdom Limited | Professional & scientific | 2006 |
| Avantishri Design and Structure Limited | Professional & scientific | 2025 |
| Avasin Limited | Hospitality | 2016 |
| Avci Business Services Ltd | Administrative & support | 2023 |
| AVE Container Lines Ltd | Transport & logistics | 2021 |
| Aveley Village (Thurrock) Management Company Limited | Households | 2013 |
| Aventura's Barbers Ltd | Health & social care | 2015 |
| Avenue NW6 Ltd | Construction | 2015 |
| Avenue Road (Banstead) Residents Management Company Limited | Households | 2005 |
| Averillo Property Management Services Limited | Professional & scientific | 2012 |
| Averillo Taxation Services Limited | Professional & scientific | 2002 |
| Avertex Ltd | Information & communication | 2026 |
| Avery Heights (Eltham) Management Company Limited | Households | 2013 |
| Avery Village Management Limited | Households | 1999 |
| Aviator Solutions Limited | Wholesale & retail | 2009 |
| Avid Solutions Limited | Professional & scientific | 2026 |
| Aviel.A Limited | Information & communication | 2014 |
| Avito 81 Ltd | Construction | 2023 |
| Avmma Properties Ltd | Real estate | 2025 |
| Avneesh Sangani Flooring Limited | Construction | 2023 |
| AVO Asset Management Ltd | Real estate | 2020 |
| Avon Bank Paddocks Limited | Households | 1990 |
| Avon Centre for Musculoskeletal Education Ltd | Education | 2015 |
| Avon View and Swan House Management Company Limited | Real estate | 2007 |
| Avonbeech Limited | Manufacturing | 2010 |
| Avowal Limited | Real estate | 2020 |
| AVR Builders Ltd | Construction | 2024 |
| AVR Maintenance Services Ltd | Construction | 2024 |
| Avram Avramov Construction Ltd | Construction | 2010 |
| AVU Consulting Ltd | Information & communication | 2025 |
| Avus Auto Ltd | Wholesale & retail | 2015 |
| AVV Plumbing Ltd | Construction | 2025 |
| AW Capital Holdings Ltd | Financial services | 2026 |
| AW Carpentry Solutions Limited | Construction | 2012 |
| AW Financial Ltd | Financial services | 2022 |
| Awais & Co Limited | Professional & scientific | 2025 |
| Awake Early Years Consultancy Ltd | Administrative & support | 2017 |
| Awans Consultants Ltd | Professional & scientific | 2023 |
| Awanstrading Limited | Wholesale & retail | 2024 |
| Award Apparel Limited | Wholesale & retail | 1992 |
| Awel Y MOR Management Company Limited | Households | 2018 |
| Awesome Investments Ltd | Real estate | 2014 |
| Awesometech Ltd | Information & communication | 2018 |
| AWL Connoisseur Group Limited | Information & communication | 2019 |
| AWO Sparkling Service Limited | Administrative & support | 2026 |
| AWO Tsidkenu CIC | Health & social care | 2025 |
| AWP Assistance UK Ltd | Financial services | 1983 |
| AWR London Limited | Manufacturing | 2012 |
| AWR London Properties Ltd | Construction | 2016 |
| Axcel Group Limited | Administrative & support | 2010 |
| Axcel Hospitality (Bath) Limited | Hospitality | 1999 |
| Axcel Hospitality (Bournemouth) Limited | Hospitality | 2020 |
| Axcel Hospitality (Edinburgh) Limited | Hospitality | 2015 |
| Axcel Hospitality (Exmouth) Limited | Hospitality | 2020 |
| Axcel Hospitality (Gatwick) Limited | Hospitality | 2019 |
| Axcel Hospitality (Inverness) Limited | Hospitality | 2019 |
| Axcel Hospitality (Lansdown) Limited | Hospitality | 2020 |
| Axcel Hospitality (Learmonth) Limited | Hospitality | 2020 |
| Axcel Hospitality (Management) Limited | Hospitality | 2017 |
| Axcel Hospitality (Manchester) Limited | Hospitality | 2015 |
| Axcel Hospitality (York) Limited | Hospitality | 2017 |
| Axel Foley Ltd | Information & communication | 2021 |
| Axhet Limited | Wholesale & retail | 2012 |
| Axia Logistics Ltd | Transport & logistics | 2009 |
| Axial Electrical Limited | Administrative & support | 2016 |
| Axim International UK Limited | Wholesale & retail | 2021 |
| Axiom Maintain Limited | Administrative & support | 1997 |
| Axion Management Ltd | Real estate | 2025 |
| Axis Holdings & Developments Ltd | Construction | 2025 |
| Axis MEP Ltd | Professional & scientific | 2026 |
| Axis Neuro Health Ltd | Health & social care | 2024 |
| Axis Point Management Limited | Households | 2009 |
| Axis Professionals Ltd | Professional & scientific | 2016 |
| Axisbridge Ltd | Wholesale & retail | 2025 |
| Axminster Recruitment Limited | Real estate | 2019 |
| Axon Aviation Charter Limited | Administrative & support | 2010 |
| Axon Aviation Partners Limited | Administrative & support | 2010 |
| Axonomy Consulting Limited | Information & communication | 2014 |
| Axtreme Counsultant Limited | Information & communication | 2025 |
| AY Residential Ltd | Real estate | 2025 |
| Ayams Group Holding Limited | Financial services | 2023 |
| Ayat Halal Meat Ltd | Wholesale & retail | 2019 |
| Ayatfutbolfc Ltd | Arts & recreation | 2025 |
| Ayazah Ltd | Wholesale & retail | 2023 |
| AYB Builders Limited | Construction | 2026 |
| Aybirk Limited | Financial services | 2024 |