| AB Automotive (Lincoln) Ltd | Wholesale & retail | 2021 |
| AB Fencing & Landscapes Ltd | Administrative & support | 2022 |
| AB Joiners Ltd | Construction | 2020 |
| AB Specialists Ltd | Administrative & support | 2025 |
| AB Speed Services Ltd | Hospitality | 2026 |
| AB Stewart Medical Services Ltd | Health & social care | 2025 |
| AB Trailer Solutions Ltd | Manufacturing | 2026 |
| Abacus A.S. Limited | Professional & scientific | 2012 |
| Abacus Hospitality Limited | Hospitality | 2014 |
| Abama Healthcare Limited | Health & social care | 2021 |
| Abba Plant Services Ltd | Extraterritorial | 1988 |
| Abbey Farming Limited | Agriculture & fishing | 1999 |
| Abbey Pilots Ltd | Transport & logistics | 2025 |
| Abbottsford Residential Management Company Limited | Households | 2011 |
| ABC House Clearance Ltd | Wholesale & retail | 2022 |
| ABC Windscreens Limited | Wholesale & retail | 2012 |
| Abel Karate Limited | Arts & recreation | 2014 |
| Aberdeen Medical Ltd | Health & social care | 2023 |
| ABF Surfacing Services Ltd | Construction | 2025 |
| Abhtho Limited | Wholesale & retail | 2026 |
| Abitails Ltd | Other services | 2024 |
| Abkneeclinic Limited | Health & social care | 2013 |
| Abn-Mb Ltd | Hospitality | 2007 |
| Abode Investments Lincoln Ltd. | Real estate | 2015 |
| Abode Management Lincoln Ltd. | Real estate | 2015 |
| Abramik Electrical Services Ltd | Construction | 2026 |
| ABS Agency Ltd | Administrative & support | 2024 |
| Absn Ltd | Transport & logistics | 2025 |
| Absolute Electrical Limited | Construction | 2023 |
| Absolute Electrical Lincoln Limited | Construction | 2017 |
| Absolutely Caterers and Events Ltd | Hospitality | 2024 |
| Absolutely Sales Ltd | Wholesale & retail | 2024 |
| Abundant Group Limited | Health & social care | 2024 |
| Abundant Healthcare Solutions Ltd | Administrative & support | 2025 |
| Abundant Housing (Support Services) CIC | Real estate | 2025 |
| Abundant Wealth Group Limited | Financial services | 2026 |
| AC 101 Ltd | Real estate | 2024 |
| AC Joinery Lincs Limited | Construction | 2017 |
| AC Roofing (Lincoln) Limited | Construction | 2011 |
| Acadafix Ltd | Professional & scientific | 2025 |
| ACC Accountancy and Taxation Ltd | Administrative & support | 2016 |
| ACC Trading Ltd | Wholesale & retail | 2023 |
| Accelerate Racing Limited | Information & communication | 2023 |
| Accentuate Consulting Group Ltd | Professional & scientific | 2023 |
| Accept Management Ltd | Arts & recreation | 2012 |
| Access Rider Training Ltd | Education | 2021 |
| Acci-Dent Smart Repairs Limited | Wholesale & retail | 2003 |
| Accile Limited | Professional & scientific | 2023 |
| Accomplish Today Limited | Administrative & support | 2014 |
| Accountancy Today Limited | Professional & scientific | 2014 |
| Accounting House International Ltd | Professional & scientific | 2025 |
| Accounting Intelligence Ltd | Professional & scientific | 2023 |
| Accuro Accounting & Business Consultants Ltd | Professional & scientific | 2025 |
| Accxia Apps Ltd | Information & communication | 2021 |
| Accxia Group Limited | Information & communication | 2016 |
| Accxia UK Limited | Information & communication | 2021 |
| Ace CAP Ltd | Real estate | 2019 |
| Ace Contract Services Ltd | Administrative & support | 2009 |
| Ace Project Incorporated Ltd | Construction | 2023 |
| Ace Road Services Ltd | Transport & logistics | 2024 |
| Ace Safety Training & Consultancy Limited | Administrative & support | 2023 |
| Ace Therapeutic Care Ltd | Public administration | 2025 |
| Ace-Noble Ltd | Health & social care | 2025 |
| ACF Acquisitions 11 Limited | Financial services | 2016 |
| ACG Consulting Ltd | Professional & scientific | 2014 |
| ACM Homes Limited | Construction | 2002 |
| Acorn Business Centres (Mansfield) Limited | Construction | 1989 |
| Acorn Partitions & Storage Systems Limited | Construction | 2000 |
| Acoustic Nations Live CIC | Arts & recreation | 2021 |
| ACP Promotions Ltd | Administrative & support | 2002 |
| Acquest Property Management Ltd | Households | 2004 |
| ACT Farming Ltd | Agriculture & fishing | 2022 |
| Action IT Theatre Company Ltd | Education | 2015 |
| Active Business Partnerships (Consultancy) Limited | Professional & scientific | 2022 |
| Active Business Partnerships Limited | Professional & scientific | 2009 |
| Active Edge Sports Therapy Limited | Arts & recreation | 2018 |
| Active Education & Sport Ltd | Information & communication | 2019 |
| Active Grow Ltd | Manufacturing | 2020 |
| Active Lincolnshire | Education | 2004 |
| Active Muslim Nation Ltd | Real estate | 2025 |
| ACTIVFR8 Ltd | Transport & logistics | 2026 |
| Actors Combat Theatrical Training Ltd | Education | 2026 |
| Acts Assured Caravan and Trailer Services Ltd | Professional & scientific | 2013 |
| Acts Trust | Education | 2006 |
| Acuity Will Writers Ltd | Professional & scientific | 2023 |
| AD Astra Management Ltd | Financial services | 2024 |
| AD Contractors Ltd | Extraterritorial | 2010 |
| AD Ortum Properties Ltd | Real estate | 2021 |
| AD Radiology Ltd | Health & social care | 2020 |
| AD Therapy Ltd | Health & social care | 2023 |
| Adagelord Limited | Real estate | 1981 |
| Adam Collins (Lincoln) Limited | Wholesale & retail | 2024 |
| Adam Evison Construction Ltd | Construction | 2022 |
| Adam Garner- Jones Properties Limited | Construction | 2025 |
| Adam Julian Marshall Ltd | Extraterritorial | 2024 |
| Adamant Corporation Ltd | Construction | 2021 |
| Adams Drywall Ltd | Construction | 2013 |
| Adams Paving Ltd | Construction | 2019 |
| Adams Shaw Limited | Manufacturing | 2004 |
| Adelincoln Intercontinental Superstore Ltd | Wholesale & retail | 2024 |