| Jill Mccracken Consulting Ltd | Professional & scientific | 2026 |
| Jimmy's Valeting Center Ltd | Administrative & support | 2025 |
| Jimohemma Services Ltd | Administrative & support | 2022 |
| Jindal Brothers Limited | Hospitality | 2024 |
| Jiosoft Ltd | Wholesale & retail | 2003 |
| Jiraff Ltd | Professional & scientific | 2021 |
| Jiritsuka Consulting Limited | Professional & scientific | 2013 |
| JJ Building Services (Mansfield) Limited | Construction | 2016 |
| Jj's Hardware Ltd | Wholesale & retail | 2025 |
| JJB Autocentre Limited | Wholesale & retail | 2026 |
| JJM Automotive Solutions Ltd | Wholesale & retail | 2021 |
| JJU Retail Limited | Wholesale & retail | 2025 |
| JK Civil Consultants Limited | Professional & scientific | 2018 |
| JK Tyres (Warsop) Limited | Wholesale & retail | 2003 |
| JKD Tyres Ltd | Wholesale & retail | 2024 |
| JKE Web Design Ltd | Professional & scientific | 2024 |
| JKS Boyles UK Group Limited | Financial services | 2022 |
| JL Home Solutions Ltd | Construction | 2025 |
| JL Supplements Ltd | Administrative & support | 2016 |
| JM (Mansfield) Limited | Manufacturing | 1990 |
| JM Building Services 1985 Limited | Construction | 2025 |
| JM Groundworks Midlands Limited | Construction | 2026 |
| JME Courier Midlands Ltd | Transport & logistics | 2025 |
| JN Orthopaedics Ltd | Health & social care | 2024 |
| JNA Ventures Ltd | Wholesale & retail | 2022 |
| JNB Flat Roofing Limited | Construction | 2020 |
| JNH Consulting Limited | Information & communication | 2017 |
| JNT19 Limited | Wholesale & retail | 2023 |
| JO Johnson Embryology Services Limited | Health & social care | 2015 |
| Joaadd Tax & Accountancy Ltd | Real estate | 2022 |
| Joanna Zajac Ltd | Transport & logistics | 2017 |
| Jobsworths (Notts) Ltd | Extraterritorial | 2021 |
| Jodanfield Ltd | Health & social care | 2024 |
| JOE Kent Ltd | Real estate | 2018 |
| JOE West Coaching Services Ltd | Arts & recreation | 2024 |
| Jofic Consultancy Limited | Information & communication | 2014 |
| John & Philip Signs and Designs Limited | Manufacturing | 2007 |
| John Coleman Ltd | Wholesale & retail | 2013 |
| John Dobb Developments Limited | Construction | 1976 |
| John J.Doe and SON Limited | Manufacturing | 1955 |
| John LEE Develops Ltd | Construction | 2023 |
| John Moseby (2019) Ltd | Financial services | 2019 |
| Johnson & Co Interiors Limited | Construction | 2023 |
| Johnson Magnetic Filters Limited | Other services | 2020 |
| Joinrite Joinery Limited | Construction | 2018 |
| Joint Forces Alliance Ltd | Health & social care | 2009 |
| Joint Health Space Ltd | Health & social care | 2024 |
| Joji Process Engineering & Project Management Limited | Professional & scientific | 2016 |
| JOK Media and Events Ltd | Manufacturing | 2025 |
| Jollys Developments Limited | Construction | 2019 |
| Jollys Investment Property Limited | Real estate | 2019 |
| Joly Cosmetics Ltd | Wholesale & retail | 2020 |
| Jomoloy Limited | Health & social care | 2024 |
| Jonathan James Limited | Real estate | 1981 |
| Jones Services Mansfield Ltd | Manufacturing | 2022 |
| Jordan River Healthcare Limited | Wholesale & retail | 2021 |
| Jordan Shack Limited | Wholesale & retail | 2026 |
| Joro Management Limited | Administrative & support | 2026 |
| Joseph Kent Ltd | Health & social care | 2020 |
| JOT Retail Limited | Wholesale & retail | 2014 |
| JOW Ltd | Information & communication | 2023 |
| Jowak Logistics Ltd | Administrative & support | 2017 |
| JP Mansion Ltd | Real estate | 2021 |
| JP Roofing Mansfield Ltd | Construction | 2026 |
| JP Swift Transport Ltd | Transport & logistics | 2025 |
| JPC LJC Property Management Ltd | Real estate | 2024 |
| JPC Property Management Services LLP | | 2020 |
| JPD Lettings Ltd | Real estate | 2015 |
| JPF Services Limited | Administrative & support | 2020 |
| JPI Real&Virtual Services Ltd | Transport & logistics | 2015 |
| JPJ Lets Ltd | Construction | 2016 |
| JPS Aquatic (UK) Ltd | Wholesale & retail | 2023 |
| JPS Associates Limited | Professional & scientific | 2022 |
| Jpsh Project Management Ltd | Information & communication | 2015 |
| JQ Griffiths Ltd | Transport & logistics | 2022 |
| JR & LJ Holdings Ltd | Administrative & support | 2025 |
| JR Eyecare Limited | Health & social care | 2019 |
| JR Lifting & Mechanical Services Ltd | Construction | 2026 |
| JR Wigley Limited | Transport & logistics | 2008 |
| JRA Bars Ltd | Hospitality | 2016 |
| JRB Accountancy Ltd | Professional & scientific | 2015 |
| JRB PRP Ltd | Real estate | 2024 |
| Jrdr Ltd | Other services | 2021 |
| Jrhh Limited | Wholesale & retail | 2024 |
| JRM Welding Ltd | Professional & scientific | 2025 |
| Jrnlettingsuk Ltd | Real estate | 2025 |
| JS Capital Group Limited | Financial services | 2026 |
| JS Fireproofing Ltd | Construction | 2021 |
| JS Patel Limited | Wholesale & retail | 2020 |
| JSB Labour Services Ltd | Construction | 2021 |
| JT CAD Services Limited | Professional & scientific | 2008 |
| JTB Driving Ltd | Transport & logistics | 2025 |
| Jtjg SPV Limited | Real estate | 2025 |
| Ju's Cafe Ltd | Hospitality | 2015 |
| Judson Signs Limited | Manufacturing | 1999 |
| Juice Stored Energy Limited | Manufacturing | 2011 |
| Julie Poulter Design Ltd | Professional & scientific | 2013 |
| Jump Entertainment Ltd | Arts & recreation | 2024 |
| Jump Events Ltd | Professional & scientific | 2020 |
| Jump Rope Media Ltd | Professional & scientific | 2026 |