| A.P. Robinson Investments | Other services | 2010 |
| A.P.R. Accident Repair Centre Ltd | Wholesale & retail | 2024 |
| A.P.T. Marine Engineering Limited | Manufacturing | 1987 |
| A.Plus Logistics Limited | Transport & logistics | 2018 |
| A.Suthrell & Partners Limited | Financial services | 1963 |
| A.T.S Construction Consultancy Limited | Construction | 2025 |
| A1 Carpentry & Construction SW Ltd | Construction | 2024 |
| A1 Scaffolding Services Ltd | Other services | 2008 |
| A1 Traffic Safety Services Limited | Transport & logistics | 2013 |
| A2 Plan Ltd | Information & communication | 2025 |
| A2B Financial Solutions Limited | Financial services | 2018 |
| A2B Software Ltd | Information & communication | 2011 |
| A2C2 Limited | Other services | 2011 |
| A2Z Medicine Management Team Ltd | Health & social care | 2024 |
| AA Auto Centre Limited | Wholesale & retail | 2003 |
| AA Lettings and Hire Limited | Construction | 2013 |
| Aaa/V Systems Ltd | Manufacturing | 2003 |
| AAC Trans Ltd | Transport & logistics | 2018 |
| Aagri Ltd. | Agriculture & fishing | 2015 |
| Aakankha Enterprises Limited | Administrative & support | 2010 |
| Aakel Pizza Limited | Hospitality | 2024 |
| Aananda Enterprise Limited | Real estate | 2024 |
| Aasilium Consulting Ltd | Information & communication | 2014 |
| AAT PS Limited | Other services | 2024 |
| AB Site Services Ltd | Professional & scientific | 2023 |
| Abab Property Limited | Construction | 2016 |
| Abacus (Lincolnshire) Limited | Real estate | 2014 |
| Abatis Fire & Security Group Ltd | Administrative & support | 2003 |
| Abbey Global Holdings Ltd | Financial services | 2010 |
| Abbey Health Care Limited | Health & social care | 2004 |
| Abbey Park at Woodhall Spa Management Company Limited | Professional & scientific | 2026 |
| Abbey Park Mews Residents' Association Limited | Households | 1993 |
| Abbey Veterinary Centre (Grimsby) Limited | Professional & scientific | 2010 |
| Abbey Windows (Goxhill) Limited | Other services | 2009 |
| Abey Developments (UK) Limited | Professional & scientific | 2005 |
| Abey Furnishing Company Limited | Wholesale & retail | 1977 |
| ABH Paints Ltd | Construction | 2026 |
| Ability Property Ltd | Real estate | 2021 |
| Ablabs Elixer Limited | Wholesale & retail | 2024 |
| Able 4 Enterprise Ltd | Construction | 2023 |
| Able BRO Limited | Wholesale & retail | 2019 |
| Able Recruitment Limited | Administrative & support | 2025 |
| ABLE4U Limited | Real estate | 2016 |
| Abode Mirrors Limited | Wholesale & retail | 2020 |
| Aboutthejob Ltd | Administrative & support | 2018 |
| Abpa Trans Ltd | Wholesale & retail | 2018 |
| Abram's Limited | Real estate | 2023 |
| Absolute Beauty Indulgence Ltd | Other services | 2015 |
| Absolute Mortgages and Protection Ltd | Financial services | 2019 |
| Abwood Contract Support Limited | Construction | 1997 |
| AC Electrical GY Limited | Manufacturing | 2015 |
| AC Joinery (Grimsby) Ltd | Construction | 2012 |
| Ac's Fresh Fish Supplies Limited | Wholesale & retail | 2002 |
| Acacia Terrace (Management Company) Limited | Households | 2012 |
| Academy at the Gate Ltd | Education | 2025 |
| Acax Limited | Information & communication | 2002 |
| Acceptable Collection Limited | Health & social care | 2022 |
| Accidental Influencer Ltd | Wholesale & retail | 2025 |
| Accolade Foods Limited | Administrative & support | 2007 |
| Accountancy Services (Lincs) Limited | Professional & scientific | 2012 |
| Accurate Cleaning Solutions Ltd | Wholesale & retail | 2008 |
| Ace of Waves Ltd | Wholesale & retail | 2024 |
| Acepace Services Limited | Administrative & support | 2016 |
| Acer Tree Care Ltd | Professional & scientific | 2024 |
| ACH Safety Ltd | Professional & scientific | 2024 |
| Achilles Centre Limited | Health & social care | 2007 |
| Achtis Ltd. | Manufacturing | 2013 |
| Aclad UK Limited | Construction | 2012 |
| ACN Services Ltd | Administrative & support | 2026 |
| Acorn Close (Healing) Management Company Limited | Households | 2017 |
| Acorn Paving Solutions Ltd | Construction | 2023 |
| Acorn Windows (Grimsby) Limited | Construction | 2008 |
| Acqr Services Limited | Other services | 2012 |
| Acre Development Group Ltd | Real estate | 2023 |
| Acrom Construction Ltd | Construction | 2020 |
| Acrom Group Limited | Financial services | 2024 |
| ACS Interiors & Joinery Ltd | Construction | 2018 |
| Actify Sports Limited | Arts & recreation | 2015 |
| Acting Lincs CIC | Arts & recreation | 2025 |
| Action Truck Parts Limited | Wholesale & retail | 2005 |
| Active Living Ltd | Wholesale & retail | 2017 |
| Actual AI Ltd | Construction | 2025 |
| AD Fryer Ltd | Hospitality | 2026 |
| AD Implant.Com Limited | Health & social care | 2007 |
| Adam JAI Investment Company Ltd | Real estate | 2020 |
| Adamir Trans Ltd | Transport & logistics | 2024 |
| Adamo Property Group Ltd | Real estate | 2020 |
| Adco Asset Holdings Ltd | Financial services | 2025 |
| Adco Crane Hire Ltd | Construction | 2024 |
| Adco Group Ltd | Financial services | 2025 |
| Adea Care Solutions Limited | Administrative & support | 2022 |
| Adec Services Ltd | Information & communication | 2008 |
| Adil Sunbeds Ltd | Other services | 2025 |
| Adir Alex Limited | Transport & logistics | 2026 |
| ADL Property Services Ltd | Construction | 2012 |
| ADM Creative Ltd | Professional & scientific | 2011 |
| Admin Essentials Ltd | Administrative & support | 2019 |
| Adri Trans Ltd | Transport & logistics | 2016 |
| Adriso Ventures Limited | Wholesale & retail | 2015 |
| Adss Truck Ltd | Transport & logistics | 2025 |