| 1 Stop Spas Ltd | Manufacturing | 2014 |
| 1-4-U Media Services Limited | Information & communication | 2012 |
| 123 Fabrics Ltd | Wholesale & retail | 2026 |
| 177 Electrical Ltd | Professional & scientific | 2019 |
| 186 Performance Ltd | Administrative & support | 2023 |
| 1ST Choice Builders Ltd | Construction | 2016 |
| 1ST Taxis Grantham Ltd | Transport & logistics | 2017 |
| 2 Ondine Road (Management Company) Limited | Households | 2010 |
| 2036 RKRF3 Ltd | Wholesale & retail | 2023 |
| 24/7 Homecare Services Limited | Health & social care | 2005 |
| 38 Albion Terrace (Sleaford) Limited | Households | 2016 |
| 3E Global Ltd | Administrative & support | 2014 |
| 445 Technology Ltd | Professional & scientific | 2018 |
| 4CORE Productions Ltd | Arts & recreation | 2024 |
| 4DY Ltd | Public administration | 2018 |
| 66 Logistics Ltd | Transport & logistics | 2017 |
| 71 Corner House Ltd | Health & social care | 2024 |
| 8 Sail Brewery Ltd | Manufacturing | 2021 |
| A & P Travel (Tours) Limited | Administrative & support | 2008 |
| A & V King Ltd | Construction | 2020 |
| A Brady Consulting Limited | Professional & scientific | 2020 |
| A F B Digital Ltd | Professional & scientific | 1999 |
| A G Banks Ltd | Transport & logistics | 2025 |
| A G SLY & Sons Limited | Agriculture & fishing | 2013 |
| A P Wood Building Ltd | Construction | 2016 |
| A R Smith LLP | | 2013 |
| A S Autos Lincoln Ltd | Wholesale & retail | 2024 |
| A T Electrical (Sleaford) Ltd | Construction | 2023 |
| A T K Transport Ltd | Transport & logistics | 2011 |
| A W Page & Co (Holdings) Limited | Financial services | 2022 |
| A&J Karan Retail Ltd | Wholesale & retail | 2026 |
| A&L Rawson Homes Ltd | Real estate | 2025 |
| A. P. Hicks Ltd | Hospitality | 2025 |
| A.B.C. (Floors) Limited | Construction | 2013 |
| A.F.K. (Holdings) Limited | Financial services | 2017 |
| A.N.Kerr Farms Limited | Agriculture & fishing | 2019 |
| A.U.H.B Dent Ltd | Health & social care | 2025 |
| A.W.Page and Co.(Seeds)Limited | Agriculture & fishing | 1968 |
| A1 Building Maintenance Ltd | Construction | 2026 |
| A1 Motor Stores (Sleaford) Ltd | Wholesale & retail | 2019 |
| Aardvark Communications Ltd | Extraterritorial | 2011 |
| AB Construction and Groundworks Ltd | Construction | 2022 |
| Abbey Independent Surveys Limited | Real estate | 2024 |
| Abbeydale Homes (Bourne) Limited | Construction | 1992 |
| ABC Stonemasonry Ltd | Manufacturing | 2024 |
| AC TC Property Ltd | Real estate | 2023 |
| Acer 68 Ltd | Real estate | 2024 |
| Active Networks & Security Systems Ltd | Administrative & support | 2014 |
| Acton Valley Developments Ltd | Construction | 2017 |
| AD Structures Limited | Professional & scientific | 2026 |
| Adaptability Solutions Ltd | Information & communication | 2026 |
| Adddzero Limited | Professional & scientific | 2023 |
| Addelsee - Smith Limited | Professional & scientific | 2002 |
| Addison Construction (Sleaford) Ltd | Construction | 2010 |
| Aded Engineering and Technologies Limited | Extraterritorial | 2024 |
| Adults Supporting Adults (ASA Shared Lives) | Health & social care | 2004 |
| Adva Trading Ltd | Wholesale & retail | 2006 |
| Adventure Lincolnshire Ltd | Education | 2018 |
| Aegidex Ltd | Information & communication | 2025 |
| Aesthetic Perfection Limited | Other services | 2020 |
| Affinity Capital Works Limited | Public administration | 2015 |
| Affinity Flying Services Limited | Public administration | 2015 |
| Affinity Flying Training Services Limited | Public administration | 2015 |
| Affinity Recycling Limited | Water & waste | 2023 |
| Agra Sleaford Ltd | Hospitality | 2024 |
| Air and Space Power Consulting Ltd | Professional & scientific | 2019 |
| Ajax Group Ltd | Wholesale & retail | 2019 |
| AJS Compliance Limited | Professional & scientific | 2016 |
| AJT Hospitality Ltd | Professional & scientific | 2023 |
| Akerman Aviation and Marine Ltd | Manufacturing | 2015 |
| Alderlance Ltd | Wholesale & retail | 2013 |
| Alexander Charles Associates Executive Search Ltd | Professional & scientific | 2016 |
| Alexander Charles Associates Ltd | Administrative & support | 2011 |
| Alexisgold Limited | Wholesale & retail | 2000 |
| Alfa Access Services Ltd | Manufacturing | 2009 |
| ALL Heat Service Limited | Construction | 2008 |
| Allerton Bradley Holdings Limited | Financial services | 2019 |
| Allerton Bradley Limited | Construction | 2019 |
| Allerton Holdings Limited | Financial services | 2019 |
| Allerton Invest Holdings Limited | Financial services | 2019 |
| Allerton Invest Limited | Other services | 2019 |
| Altom Holdings Limited | Real estate | 2021 |
| AM ENT Ltd | Health & social care | 2015 |
| Ambak Ltd | Construction | 2019 |
| Ambrey Baker Industrial Solutions Ltd | Construction | 2006 |
| Anderson Farms Limited | Agriculture & fishing | 1988 |
| Andrew Wade Ltd | Health & social care | 2010 |
| Andy ROY Limited | Construction | 2008 |
| Andy Snax Ltd | Hospitality | 2024 |
| Anglia Medicals Ltd | Health & social care | 2010 |
| Anglian EYE Limited | Professional & scientific | 2015 |
| Anglo-Sino Heritage Technology Ltd | Professional & scientific | 2021 |
| Animal Doctor Limited | Professional & scientific | 2014 |
| Anwick Forge Ltd | Manufacturing | 2017 |
| Anwick Manor Management Company Limited | Households | 2021 |
| Aorta the Heart of Art Limited | Manufacturing | 2014 |
| Appetites Food Company Limited | Hospitality | 2019 |
| Apricis Tugurio Ltd | Hospitality | 2021 |
| Aqva Hydro Ltd | Professional & scientific | 2020 |
| AR Truck & Tyre Ltd | Manufacturing | 2026 |