| 20-20 Site Management Ltd | Extraterritorial | 2020 |
| 20/20 Cleaning Ltd | Administrative & support | 2007 |
| 21 GTX Limited | Manufacturing | 2024 |
| 23 Coffee Ltd | Hospitality | 2024 |
| 23BAKEHOUSE Ltd | Manufacturing | 2025 |
| 2K Management Services Limited | Professional & scientific | 2014 |
| 3 I Training Limited | Professional & scientific | 1999 |
| 3CDR Trading Limited | Wholesale & retail | 2017 |
| A & L Kirby Property Ltd | Administrative & support | 2015 |
| A O Pharma Services Ltd | Professional & scientific | 2022 |
| A&C Maintenance Solutions Cleaning Ltd | Administrative & support | 2025 |
| A. G. a. C. Limited | Real estate | 2004 |
| A.G.A.C Holdings Limited | Financial services | 2019 |
| A.T. Jenkins Limited | Construction | 1964 |
| A1 Safety Training Limited | Professional & scientific | 2017 |
| A815 Limited | Professional & scientific | 2021 |
| AA Housing Services Ltd | Real estate | 2024 |
| Abbey Academies Trust | Education | 2010 |
| Abbey Road Kitchen Limited | Hospitality | 2022 |
| Abbey' Stone & Masonry Limited | Construction | 1999 |
| ABS Logistic Solutions Limited | Transport & logistics | 2018 |
| Absolute Plumbing and Heating (Bourne) Limited | Construction | 2017 |
| Accessible Coders Community Interest Company | Education | 2014 |
| Acert Limited | Education | 2015 |
| ACM Marketing Consultancy Limited | Professional & scientific | 2007 |
| AD Fire Safety Ltd | Administrative & support | 2022 |
| Adara UK Ltd | Wholesale & retail | 2021 |
| Adbex Properties Limited | Real estate | 2022 |
| Admatics Control Systems LLP | | 2010 |
| Admiral VOO Ltd | Information & communication | 2021 |
| Advanced Concrete Protection Limited | Construction | 1997 |
| Advanced Digital Associates Ltd | Information & communication | 2025 |
| Adventure Growth Partners Ltd | Information & communication | 2025 |
| AE Technical Production Limited | Administrative & support | 2020 |
| Aerodyne Global Limited | Manufacturing | 2015 |
| Aerodyne Group Limited | Financial services | 2015 |
| AES 2014 Ltd | Transport & logistics | 2024 |
| Ag.Wgcddne Ltd | Information & communication | 2022 |
| AGE Care Advice Limited | Health & social care | 2014 |
| Agile Engineering Ltd | Manufacturing | 2024 |
| Agri-Linc Holdings Limited | Financial services | 2017 |
| Agri-Linc Limited | Wholesale & retail | 2017 |
| AGT Accounting Limited | Professional & scientific | 2026 |
| AGT Property Services Limited | Real estate | 2021 |
| Ailsby Limited | Professional & scientific | 2007 |
| AJ Catering and Bars Ltd | Hospitality | 2023 |
| AJ Digital Creative Limited | Professional & scientific | 2019 |
| AJS Consulting Ltd | Professional & scientific | 2025 |
| Alexa Transport Services Ltd | Transport & logistics | 2021 |
| Alexandra Property Group Ltd | Real estate | 2018 |
| Alexandru Ciobotoiu Ltd | Transport & logistics | 2017 |
| Ali's Angels Ltd | Administrative & support | 2021 |
| ALL About Mortgages Limited | Financial services | 2023 |
| Allcow Trading Company Limited | Professional & scientific | 2011 |
| Allgreen Designs Ltd | Manufacturing | 2011 |
| Allprep Ltd | Hospitality | 2022 |
| Alpha Garden Rooms Ltd | Construction | 2023 |
| Alphen Limited | Professional & scientific | 2015 |
| Amazing Shirts Ltd | Wholesale & retail | 2020 |
| AMC Property Consultancy Limited | Mining & quarrying | 2004 |
| Amcot Limited | Professional & scientific | 2001 |
| AMJ Connect Ltd | Information & communication | 2025 |
| Amsaa Limited | Administrative & support | 2008 |
| Andrew Morley Business Consultancy Ltd | Professional & scientific | 2021 |
| Anglo American Media Limited | Information & communication | 1998 |
| Ankocleans Limited | Administrative & support | 2025 |
| Anna & Co Barbers Ltd | Other services | 2023 |
| Annona AG Limited | Agriculture & fishing | 2015 |
| ANP Primary Care Solutions Ltd | Health & social care | 2022 |
| Anti-Bored Sourcing Ltd | Other services | 2025 |
| Antos Trans Ltd | Transport & logistics | 2021 |
| Aperitivo Bars Limited | Hospitality | 2017 |
| Apolo Trading Ltd | Wholesale & retail | 2026 |
| Apply Additive Consultants Ltd | Professional & scientific | 2024 |
| Approved Maintenance Services Ltd | Construction | 2022 |
| April Yardley Education Ltd | Other services | 2022 |
| APS01 Ltd | Real estate | 2025 |
| Aqres Ltd | Other services | 2022 |
| Aquarium Composition Ltd | Construction | 2020 |
| Aquatic Impact Limited | Construction | 2007 |
| Archanous Ltd | Information & communication | 2026 |
| Ardena Homes Limited | Construction | 2022 |
| Areebah Noor Ltd | Hospitality | 2022 |
| Aremi Limited | Extraterritorial | 2000 |
| Argent Technical Services Ltd | Professional & scientific | 2008 |
| Arize Care Ltd | Public administration | 2024 |
| Armstrong Property Solutions Ltd | Financial services | 2025 |
| Arrow of Bourne Ltd | Wholesale & retail | 2016 |
| Arrow Ventures Limited | Extraterritorial | 2019 |
| Artedo Ltd | Transport & logistics | 2021 |
| ASC Automotive Ltd | Wholesale & retail | 2021 |
| ASH Katalogue Ltd | Professional & scientific | 2026 |
| Ashley Harrison Ltd | Administrative & support | 2023 |
| Ashton Holdings Bourne Limited | Construction | 2025 |
| Ashwell Communities Limited | Construction | 2017 |
| Ashwell Old Co MID Co Ltd | Administrative & support | 2017 |
| Aspire Carpentry Limited | Manufacturing | 2022 |
| Aspire to BE International Limited | Professional & scientific | 2004 |
| Asrm Properties Ltd | Real estate | 2025 |
| Assetright Ltd | Professional & scientific | 2013 |