| Brian Fairweather Autos Ltd | Wholesale & retail | 2012 |
| Brian Fish & Chips Ltd | Hospitality | 2019 |
| Brickrentals Ltd | Wholesale & retail | 2026 |
| Bridge Farm Caravan Park Limited | Hospitality | 2021 |
| Bridge View Osteopaths Limited | Health & social care | 2011 |
| Brigadier Limited | Professional & scientific | 2022 |
| Briggs & Skinner Ltd | Wholesale & retail | 2014 |
| Bright Medical Limited | Real estate | 2011 |
| Bright Sparks Kindergarten Ltd | Education | 2007 |
| Brilliant GP Ltd | Health & social care | 2023 |
| Britannia Business Ventures Limited | Wholesale & retail | 2026 |
| Britannia Coffee Limited | Wholesale & retail | 2022 |
| Britannia Prime Freight Ltd | Transport & logistics | 2024 |
| Brittonian Limited | Financial services | 2017 |
| Britz Corporation Ltd | Wholesale & retail | 2026 |
| BRM Developments Ltd | Real estate | 2005 |
| Broad Street Apartments Limited | Households | 2004 |
| Broadgate Investments Limited | Real estate | 2025 |
| Broadley Home Maintenance Ltd | Construction | 2023 |
| Brooks & Kirk Limited | Education | 2011 |
| Brooks and Kirk (Assessor Training) Limited | Education | 2015 |
| Brooks and Kirk Digital Ltd | Other services | 2019 |
| Brothers C.O Solutions Ltd | Construction | 2025 |
| Brothertoft Build Limited | Construction | 2007 |
| Brothertoft Livestock Limited | Agriculture & fishing | 2021 |
| Brown Rudnick LLP | | 2023 |
| BRP Trevor Limited | Construction | 2002 |
| Bruce Mather Limited | Real estate | 2006 |
| Bruno Properties Ltd | Real estate | 2017 |
| Bubble & Bash Ltd | Other services | 2025 |
| Bubbly Bubble Tea Ltd | Wholesale & retail | 2025 |
| Buddex UK Ltd | Real estate | 2025 |
| Bulldog Scaffolding (Boston) Ltd | Construction | 2024 |
| Bullhorn International, Inc. | | 2010 |
| Burton Corner Management Company Limited | Professional & scientific | 2002 |
| Burton Dental Lodge Ltd | Health & social care | 2014 |
| Burton Lodge Assets Ltd | Real estate | 2021 |
| Businesses in Distress Support Ltd | Professional & scientific | 2023 |
| Busytyc Ltd | Transport & logistics | 2024 |
| Butautas Limited | Transport & logistics | 2022 |
| Butterwick FRY Ltd | Hospitality | 2024 |
| Butterwick Stores Ltd | Wholesale & retail | 2024 |
| BV Fabrications Limited | Manufacturing | 2012 |
| BVG (Lincs) Limited | Professional & scientific | 2013 |
| BW HVS Ltd | Professional & scientific | 2023 |
| BWP (BBM) Management Ltd | Wholesale & retail | 2019 |
| C & P Transport (Lincs) Ltd | Transport & logistics | 2025 |
| C E M Consortium Limited | Construction | 2012 |
| C E Myland Ltd | Real estate | 2025 |
| C J & K L Properties Ltd | Real estate | 2010 |
| C J a S S Limited | Real estate | 2020 |
| C V Larissa Limited | Hospitality | 2022 |
| C&H Garden Maintenance Ltd | Administrative & support | 2023 |
| C.& R.Needham Limited | Agriculture & fishing | 1964 |
| C.W. Vinter (Wigtoft) Limited | Real estate | 1972 |
| CA Properties (Lincolnshire) Limited | Real estate | 2025 |
| CA Tree Services Limited | Other services | 2019 |
| Cabin Fever Ltd | Information & communication | 2013 |
| Cabletronics Limited | Manufacturing | 2001 |
| Caerlaverock Ltd | Health & social care | 2019 |
| Cafe Noglish Ltd. | Hospitality | 2020 |
| Cain-Smith Decorating Ltd | Construction | 2022 |
| Calders & Grandidge (Boston) Limited | Manufacturing | 2020 |
| Caleb 1969 Limited | Extraterritorial | 2013 |
| Calimathi GSD Limited | Other services | 2019 |
| Call for Cabs Ltd | Transport & logistics | 2024 |
| Calm Mind Studio Asmr Ltd | Other services | 2025 |
| Calm Steps Community Project CIC | Health & social care | 2025 |
| Calm Steps Ltd | Education | 2024 |
| Calverton Greens Boston Ltd | Wholesale & retail | 2016 |
| Camilon Group Ltd | Agriculture & fishing | 2008 |
| CAMPERVAN2GO Ltd | Administrative & support | 2025 |
| CAN Kusmus Ltd | Hospitality | 2025 |
| CAN Salik Advisory Limited | Transport & logistics | 2021 |
| Canine Hoopers International Ltd | Education | 2020 |
| Capital Ashman Ltd | Other services | 2026 |
| Captain Patila Limited | Hospitality | 2023 |
| Captan Ltd | Wholesale & retail | 2021 |
| Car Repairs (Boston) Ltd | Wholesale & retail | 2022 |
| Caraibe Ltd | Administrative & support | 2017 |
| Cardecho Limited | Health & social care | 2017 |
| Cardiotec Ltd | Health & social care | 2017 |
| Care Concern Solutions Ltd | Other services | 2025 |
| Care Home Entertainment Limited | Arts & recreation | 2017 |
| Care Kind 24/7 Ltd | Health & social care | 2023 |
| Care Plas Limited | Health & social care | 2019 |
| Care Plas Services Ltd | Health & social care | 2017 |
| Carmel Green Management Company Limited | Other services | 1983 |
| Carniluxe (RAW) Ltd | Manufacturing | 2018 |
| Caroline Bray Limited | Hospitality | 2023 |
| Carousel Lights Limited | Manufacturing | 2013 |
| Carr Funeral Service (Boston) Limited | Other services | 1981 |
| Carrington Rally | Other services | 2011 |
| Castillo Plant Hire and Sales Ltd | Construction | 2025 |
| Castle Property Rental Limited | Administrative & support | 2006 |
| Castle-Communications Limited | Information & communication | 2024 |
| Castleautumn Limited | Real estate | 2000 |
| Castlebeck Homes Ltd | Construction | 2024 |
| Castledyke Equestrian Centre Limited | Education | 2009 |
| Castledyke Swimming Pool Ltd | Arts & recreation | 2024 |