| Baxter Sussex Limited | Eastbourne | 1999 |
| Baxter's Holdings Limited | Hitchin | 1942 |
| Baxters (Properties) Limited | Lichfield | 1933 |
| Bay 28 Ltd | Bodmin | 2017 |
| Bay Bidco Limited | Elland | 2024 |
| Bay Bionics Ltd | London | 2020 |
| Bay Capital Partners UK Limited | London | 2006 |
| Bay Care Group Holdings Ltd | Torquay | 2024 |
| Bay Care Ventures Ltd | Torquay | 2024 |
| Bay Collective UK Limited | London | 2025 |
| Bay Consulting & Management Ltd | Beverley | 2025 |
| Bay Crescent Company Limited | Cookstown | 2021 |
| Bay Financial Planning Ltd | Dalgety Bay | 2023 |
| Bay Financial Solutions Ltd | Herne Bay | 2023 |
| Bay Hale Investments Ltd | Hertford | 2023 |
| Bay Holdco Limited | Elland | 2024 |
| Bay Horse Marketing Services Limited | Kirk Deighton Leeds | 1989 |
| Bay Leaf Paraplanning Services Ltd | Whitley Bay | 2015 |
| Bay Marine Insurance Consultants Limited | Cardiff | 2003 |
| Bay Midco Limited | Elland | 2024 |
| Bay Middleton Capital Ltd | Epsom | 2024 |
| Bay ST Louis Holdings Limited | Newry | 2023 |
| Bay Staffing Limited | Stafford | 2023 |
| Bay Topco Limited | Elland | 2024 |
| Bay Tree Finance Ltd | Warrington | 2024 |
| Bay Tree Helios Nominee Limited | Billingshurst | 2018 |
| Bay Tree Interiors (Holdings) Limited | Nottingham | 2006 |
| Bay UK Energy Services Limited | London | 2025 |
| Baya Financial Ltd | Birmingham | 2018 |
| Bayagan Holdings Limited | Brighton | 2022 |
| Bayan Holdings Ltd | Harrow | 2026 |
| Bayarcal Holding Limited | Manchester | 2022 |
| Bayard Capital (UK) Limited | Kettering | 2013 |
| Bayard Management (UK) Limited | London | 2021 |
| Bayards Property Holdings Limited | Worthing | 2025 |
| Baybayon Ltd | London | 2016 |
| Baybutt Investments Limited | Preston | 2016 |
| Bayco Holdings Ltd | Bingham | 2025 |
| Baycup Limited | Glasgow | 2023 |
| Baydon Capital Limited | Southampton | 2024 |
| Bayelsa Development & Investment Company Ltd | Barking | 2013 |
| Bayen Capital Ltd | London | 2022 |
| Bayes Alpha Limited | London | 2020 |
| Bayes Investments Limited | London | 2014 |
| Bayesian Shift Ltd | London | 2019 |
| Bayfields (Harrogate) Holdings Dormant Limited | Shipley | 2016 |
| Bayfields Group Limited | Shipley | 2013 |
| Bayford Energy Bidco Limited | Wetherby | 2020 |
| Bayford Energy Holdco Limited | Wetherby | 2020 |
| Bayham Street Financial Limited | Stanmore | 2014 |
| Bayhead Advisers Limited | London | 2015 |
| Bayhouse Holding Co | Ware | 2022 |
| Baykers Holdings Ltd | Rowland'S Castle | 2023 |
| Bayleaf Holdings Limited | London | 2020 |
| Bayley Assets Limited | Bournemouth | 2020 |
| Bayley Holdings Ltd | Haverhill | 2020 |
| Bayley House Limited | London | 2024 |
| Baylis (Gloucester) Holdings Limited | Cheltenham | 2020 |
| Bayliss & Co. (Financial Services) Limited | Nr Banbury | 1986 |
| Bayliss and Co.(Wealth Management) Limited | Stourbridge | 2011 |
| Bayliss Group Ltd | Bromsgrove | 2026 |
| Bayliss Projects SPV 1 Limited | Llandradach | 2023 |
| Bayliss Recovery (Holdings) Limited | Newport | 2015 |
| Baylog Holding Limited | London | 2016 |
| Baylon Philips Financial Solutions Ltd | Norwich | 2017 |
| Baylore Ltd | Gerrards Cross | 2009 |
| Baynor Capital Limited | London | 2023 |
| Baynoun Enterprises Limited | London | 2015 |
| Bayntum Limited | Chippenham | 2024 |
| Bayport Africa Midco Limited | London | 2024 |
| Bayport Intermediate Holdco PLC | London | 2024 |
| Bayport Latam Midco Limited | London | 2024 |
| Bayprod Holdings Limited | Cardiff | 2013 |
| Bayridge Investments Ltd | Newcastle Upon Tyne | 2024 |
| Bayshore Drive Holdings Limited | Southampton | 2025 |
| Bayside Capital Limited | Maidstone | 2026 |
| Bayside Estates Sales and Lettings Ltd | Treharris | 2013 |
| Bayside Finance Ltd | Lee-On-The-Solent | 2025 |
| Bayside Holdings Limited | Hatfield | 2021 |
| Baystone Ventures Limited | Scarborough | 2024 |
| Baysurf Limited | Nottingham | 1997 |
| Bayswater Bank Limited | Leeds | 2006 |
| Bayswater Property Group Limited | London | 2023 |
| Bayt Altamweel Aldawali Ltd | London | 2015 |
| Bayt Financial Limited | London | 2024 |
| Bayt Investment Limited | Romford | 2020 |
| Bayt Sajj Holdings Ltd | London | 2023 |
| Bayt Stone Holdings Limited | Leicester | 2024 |
| Bayte Limited | Stamford | 2014 |
| Baytech Business Solutions PVT Ltd | Cardiff | 2025 |
| Bayton Bidco Limited | London | 2019 |
| Bayton Debtco Limited | London | 2019 |
| Bayton Midco Limited | London | 2019 |
| Bayton Properties Limited | | 1960 |
| Bayton Topco Limited | London | 2019 |
| Baytor Holdings Limited | Newton Abbot | 2025 |
| Baytree Adventures Limited | Dudley | 2022 |
| Baytree Investment Group Ltd | Derby | 2019 |
| Baytree Media Group Limited | New Malden | 2017 |
| Baytree Private Investments Limited | London | 2025 |