| 3 HB Limited | Administrative & support | 2018 |
| 44 Lift Co. Ltd | Wholesale & retail | 2026 |
| 51 Wide Bargate Management Company Limited | Hospitality | 2001 |
| 617 Limited | Hospitality | 2012 |
| A & D Wilkins Limited | Professional & scientific | 1999 |
| A & R Cramphorn Plant Hire Limited | Administrative & support | 2004 |
| A & S Critical Services Limited | Education | 2004 |
| A B Electrical & Refrigeration Limited | Construction | 2004 |
| A K Gray Site Services Limited | Administrative & support | 2006 |
| A L Garages (Lincs) Limited | Wholesale & retail | 2003 |
| A P S Printers Limited | Manufacturing | 2004 |
| A R Siddans Limited | Construction | 2005 |
| A. Parsonson Limited | Agriculture & fishing | 2004 |
| A. Poucher and Sons (Bardney Dairies) Limited | Agriculture & fishing | 1978 |
| A.E. Culley (Architectural Services) Limited | Professional & scientific | 2003 |
| A.F.K. (Marketing) Limited | Manufacturing | 1991 |
| A.R.Properties (Stamford) Ltd | Real estate | 2003 |
| A1 Infrastructure and Building Limited | Construction | 2006 |
| A1 Statics Ltd | Wholesale & retail | 2023 |
| Aasma Wardrobe Ltd | Wholesale & retail | 2025 |
| ABC First AID & Safety Training Ltd | Health & social care | 2007 |
| ABC Surveying Limited | Extraterritorial | 2004 |
| Absailing NDT Ltd | Mining & quarrying | 2025 |
| Accolade Print Media Limited | Manufacturing | 2004 |
| Ace Financial Advisers Limited | Financial services | 2006 |
| Acorn Contract & Hire Limited | Transport & logistics | 2002 |
| Acorn Financial Services Limited | Financial services | 2006 |
| ACP Connect Ltd | Other services | 2004 |
| Addison Elec Contracting Ltd | Construction | 2019 |
| Adogranonthepitch Limited | Construction | 2003 |
| Adrra Associates Limited | Wholesale & retail | 2005 |
| Affordable Furniture Limited | Wholesale & retail | 2001 |
| Agatha Clothing Limited | Wholesale & retail | 2002 |
| Agri.Cycle Limited | Water & waste | 2004 |
| AJB Plumbing and Heating Limited | Construction | 2005 |
| Ajet GB Limited | Administrative & support | 2006 |
| Al-Aqsa Supermarkets Limited | Wholesale & retail | 2007 |
| Alan Dixon Limited | Transport & logistics | 1993 |
| Albany Guest House Limited | Hospitality | 2005 |
| Alford Traffic Limited | Transport & logistics | 2003 |
| ALL Seasons Window Films Limited | Construction | 2003 |
| Allan Haddow Limited | Education | 2000 |
| Allen Roofing Ltd | Construction | 2005 |
| Allerton Construction Limited | Financial services | 1974 |
| Allround Recruitment Solutions Limited | Professional & scientific | 2006 |
| Alpha Glass (Southend) Limited | Real estate | 1978 |
| AMA Smiles Ltd | Health & social care | 2023 |
| Ambassador Window Systems Limited | Construction | 2006 |
| Amberely Limited | Transport & logistics | 1991 |
| Amea Consultants Limited | Professional & scientific | 2005 |
| Andrew J Clark Limited | Construction | 2004 |
| Angel Light Studio Ltd | Information & communication | 2024 |
| Angloflora Limited | Professional & scientific | 2001 |
| Ankara Hukuk Ltd | Financial services | 2025 |
| Annakin Farms Limited | Agriculture & fishing | 1997 |
| Apex Roofing (UK) Ltd | Construction | 2008 |
| Appetites Limited | Hospitality | 2002 |
| Ashdene Sleaford Limited | Health & social care | 1995 |
| Ashrise Properties Limited | Mining & quarrying | 2003 |
| AT Source QX Limited | Manufacturing | 1999 |
| Atsaa Family Ltd | Hospitality | 2024 |
| Aumika Ltd | Real estate | 2023 |
| Aurum Comps UK Ltd | Other services | 2026 |
| Automasion Ltd | Information & communication | 2025 |
| Avison Machinery Ltd | Wholesale & retail | 2025 |
| Avison Properties Ltd | Real estate | 2025 |
| Awin Barratt Siegel Wine Agencies LLP | | 2004 |
| Axis Surveys Limited | Real estate | 1999 |
| B & H Excavators Limited | Construction | 2003 |
| B O'Rourke Groundworks Ltd | Construction | 2003 |
| B. a. Bush (Tyres) Limited | Wholesale & retail | 1973 |
| B.J. Covell & Sons Limited | Agriculture & fishing | 1975 |
| Baileys Garden Services Ltd | Other services | 2002 |
| Bakehouse 105 Limited | Real estate | 2012 |
| Baldwin M&E Ltd | Professional & scientific | 2024 |
| Banger's Cafe Limited | Hospitality | 2024 |
| Barnes Taxis Limited | Transport & logistics | 2008 |
| Basarabia Ltd | Wholesale & retail | 2023 |
| Baumber Park Farms Limited | Agriculture & fishing | 2007 |
| Beam Estate Agents Ltd | Real estate | 2007 |
| Beckingham Greenfuels Ltd | Extraterritorial | 2007 |
| Beckside Commercial Property Company Limited | Real estate | 1993 |
| Bell Brothers Nurseries Limited | Wholesale & retail | 2001 |
| Bells Convenient Store Ltd | Wholesale & retail | 2021 |
| Belvoir Builders (Grantham) Limited | Real estate | 1987 |
| Benman Brown Accountants Ltd | Professional & scientific | 2005 |
| Bernie Morris Limited | Wholesale & retail | 2006 |
| Bews Brown & Partners Limited | Real estate | 2005 |
| BGB Engineering Limited | Manufacturing | 1987 |
| Bigvale Investments Limited | Professional & scientific | 1962 |
| Blrt Limited | Other services | 2002 |
| Blue Oak Merchandising Limited | Wholesale & retail | 2003 |
| Booped Limited | Information & communication | 2004 |
| Booth Parkes & Associates Limited | Professional & scientific | 1994 |
| Boston and County Club Limited(The) | Hospitality | 1948 |
| Boston United Football Club Limited | Arts & recreation | 1935 |
| Boston Van Hire Limited | Wholesale & retail | 1998 |
| Boston West END Bowling Club Limited | Arts & recreation | 1947 |
| Boud Minerals & Polymers Limited | Manufacturing | 1999 |
| Boud Minerals Limited | Manufacturing | 1985 |