| Atlantic Pumps Group Limited | Chesterfield | 2024 |
| Atlantic Refrigeration Group Holdings Limited | Lee On Solent | 2024 |
| Atlantic Refrigeration Holdings Limited | Lee On Solent | 2012 |
| Atlantic Regeneration 1 Nominee 1 Limited | Fareham | 2012 |
| Atlantic Regeneration 1 Nominee 2 Limited | Fareham | 2012 |
| Atlantic Regeneration 1 Security Agent Limited | Fareham | 2012 |
| Atlantic Regeneration Property 1 General Partner Limited | Fareham | 2012 |
| Atlantic Road Holdings Limited | Bath | 2025 |
| Atlantic SAV 2 Limited | London | 2020 |
| Atlantic SAV Limited | London | 2005 |
| Atlantic Series 2025-01 Limited | London | 2025 |
| Atlantic Shield Ltd | Manchester | 2025 |
| Atlantic Timber Holdings Limited | Manchester | 2015 |
| Atlantic Topco Limited | Houghton Le Spring | 2018 |
| Atlantic UK Bidco Limited | London | 2024 |
| Atlantic UK Insurance and Reinsurance Brokers Ltd | London | 2016 |
| Atlantic Venture Capital + Ltd | London | 2023 |
| Atlantic Wealth Management (UK) Limited | Chelmsford | 2013 |
| Atlantic Wealth Management Limited | 1 Oxford St | 1978 |
| Atlantic Worldwide, Inc. Ltd | London | 2021 |
| Atlantic XL International Limited | Aberdeen | 2021 |
| Atlantica Development UK Limited | London | 2019 |
| Atlantica Global Ltd | London | 2022 |
| Atlantica Holdco Limited | London | 2024 |
| Atlantica Holdings UK Limited | London | 2019 |
| Atlantica Investments Limited | London | 2018 |
| Atlantica Midco Limited | London | 2024 |
| Atlantica Sustainable Infrastructure Group PLC | London | 2024 |
| Atlantica Wealth Administration Ltd | Castle Cary | 2019 |
| Atlanticomnium (UK) Limited | Cambridge | 2011 |
| Atlantida Advisers Limited | London | 2022 |
| Atlantida Corporation Limited | London | 2022 |
| Atlantida International Holdings Limited | London | 2022 |
| Atlantida Thames Holdings Limited | London | 2023 |
| Atlantide Asset Management Limited | London | 2011 |
| Atlantique Consulting Ltd | Ilford | 2009 |
| Atlantis Acquisition Company Limited | Llanelli | 2025 |
| Atlantis Diffusion Ltd | Bristol | 2013 |
| Atlantis Estates Ltd | London | 2015 |
| Atlantis Finance Limited | Birmingham | 2025 |
| Atlantis Financial Services Ltd | London | 2020 |
| Atlantis Forwarding Holdings Limited | Leeds | 2007 |
| Atlantis Future Energy PLC | London | 2018 |
| Atlantis Group Holdings Limited | Kilmarnock | 2025 |
| Atlantis Holdings (N.I.) Limited | Armagh | 2018 |
| Atlantis Money Box Ltd | Birmingham | 2021 |
| Atlantis Ocean Energy PLC | London | 2017 |
| Atlantis Office Group Limited | Witham | 2024 |
| Atlantis Systems Ltd | London | 2022 |
| Atlantis Wine Holdings Limited | London | 1993 |
| Atlantisllc Limited | London | 2025 |
| Atlantix Associates Ltd | Worcester Park | 2010 |
| Atlas Financial Consulting Limited | Stonehaven | 2001 |
| Atlas & Co Mortgage Services Limited | Bingley | 2025 |
| Atlas & Co. Ltd | London | 2026 |
| Atlas (AHL) Holdings Limited | Brighton | 2023 |
| Atlas 1 Holdings Ltd | Watford | 2026 |
| Atlas 2026 Bidco Limited | Birmingham | 2026 |
| Atlas 2026 Holdco Limited | Birmingham | 2026 |
| Atlas 2026 Midco Limited | Birmingham | 2026 |
| Atlas 2026 Topco Limited | Birmingham | 2026 |
| Atlas 25 Bidco Limited | Polegate | 2025 |
| Atlas 25 Midco 1 Limited | Polegate | 2025 |
| Atlas 25 Midco 2 Limited | Polegate | 2025 |
| Atlas 25 Topco Limited | Polegate | 2025 |
| Atlas 2U Ltd | Sheffield | 2017 |
| Atlas Acquisitions Group Ltd | Birmingham | 2022 |
| Atlas Advisory Group Ltd | London | 2025 |
| Atlas Assets Global Ltd | London | 2022 |
| Atlas Aston Limited | Slough | 2023 |
| Atlas Bidco 1 Limited | London | 2021 |
| Atlas Bidco Limited | London | 2020 |
| Atlas Bridge Capital Ltd | London | 2025 |
| Atlas Bridging Limited | Brighton | 2023 |
| Atlas Business Finance Ltd | Sherington | 2022 |
| Atlas Capital Group Limited | London | 2025 |
| Atlas Capital Holdings Ltd | Taunton | 2025 |
| Atlas Card Services Limited | Washington | 2018 |
| Atlas Care Homes Group II Limited | London | 2025 |
| Atlas Clever Consultants Limited | Denmead | 2017 |
| Atlas Commercial Finance Ltd | Birmingham | 2026 |
| Atlas Commercial Property Investments Limited | Datchet | 2018 |
| Atlas Commodity Group Ltd | London | 2026 |
| Atlas Consolidated (UK) Ltd | London | 2025 |
| Atlas Consultancy Services Ltd | Seaton | 2016 |
| Atlas Contract Furniture Holdings Ltd | Christchurch | 2018 |
| Atlas Corporate Holdings Ltd | Wellington | 2018 |
| Atlas Courier Express (Holdings) Limited | Leigh On Sea | 2018 |
| Atlas CPI Benfleet Limited | Slough | 2023 |
| Atlas Currency Exchange Ltd | London | 2026 |
| Atlas Deals Ltd | London | 2022 |
| Atlas Digital Assets Limited | London | 2025 |
| Atlas Display Holdings Limited | Huddersfield | 2019 |
| Atlas Dominium Holdings Ltd | London | 2026 |
| Atlas Eass Ltd | London | 2025 |
| Atlas Edge Ltd | London | 2025 |
| Atlas Equity Holdings Ltd | Ashford | 2025 |
| Atlas Equity Ltd | London | 2020 |
| Atlas Family Partners Limited | Milton Keynes | 2015 |
| Atlas Finance (Scotland) Limited | Glasgow | 2011 |