| Lawrentas Healthcare Ltd | Administrative & support | 2026 |
| Laxfield Community Land Trust Limited | Professional & scientific | 2019 |
| Laxfield Community Market CIC | Wholesale & retail | 2023 |
| Laxfield Literary Associates Ltd | Information & communication | 2020 |
| Lazy Acres Properties Limited | Real estate | 2022 |
| Lb&Co Ltd | Information & communication | 2026 |
| LCB Woodbridge Limited | Real estate | 2017 |
| LE42N Ltd | Professional & scientific | 2015 |
| Leadership 43 Ltd | Professional & scientific | 2020 |
| Leadership Physic(K)S Limited | Administrative & support | 2004 |
| Leasehold Central Limited | Information & communication | 2019 |
| Leigh's Forestry & Firewood Ltd | Agriculture & fishing | 2013 |
| Lemon Drizzle Limited | Hospitality | 2016 |
| Leo's Delicatessen Limited | Wholesale & retail | 2014 |
| LET the KID DIG Ltd | Arts & recreation | 2023 |
| Letsby Avenue Limited | Real estate | 2015 |
| Levis (Holdings) Limited | Real estate | 1913 |
| Lewis Culf Group Limited | Real estate | 2024 |
| Lewis Culf Ltd | Construction | 2011 |
| Lifestone Investments Limited | Financial services | 2019 |
| Light Between Limited | Administrative & support | 2010 |
| Lighthouse (Training and Development) Ltd | Professional & scientific | 2011 |
| Lighthouse Optics Limited | Administrative & support | 2014 |
| Lightning Craft Ltd | Manufacturing | 2020 |
| Lignum Limited | Administrative & support | 2012 |
| Lime Residential Limited | Real estate | 2006 |
| Lime Thorne Ltd. | Professional & scientific | 1999 |
| Limpet Properties Limited | Construction | 1997 |
| Lingwold Limited | Real estate | 1983 |
| Lion Family Properties Limited | Financial services | 2022 |
| Lion Herba LLP | | 2014 |
| Lippizaner (Easton) Limited | Real estate | 2011 |
| Little Leaders Group Ltd | Health & social care | 2025 |
| Littleoakparks Ltd | Education | 2020 |
| LIZ Wilkins Ltd | Professional & scientific | 2017 |
| LJD Recruitment Ltd | Administrative & support | 2015 |
| LJH Consulting Ltd | Professional & scientific | 2013 |
| LJH Properties Ltd | Real estate | 2015 |
| LL Management Solutions Ltd | Administrative & support | 2022 |
| Lloyd Building and Joinery Limited | Construction | 2006 |
| Lloyd Consultancy Group Limited | Information & communication | 2024 |
| LM Cuts Ltd | Other services | 2025 |
| Locam Ltd | Professional & scientific | 2022 |
| Lockhart Leisure (Ipswich) Limited | Wholesale & retail | 2021 |
| Lockhart Leisure (Services) Limited | Professional & scientific | 2008 |
| Lockhart Lettings Limited | Real estate | 2020 |
| Lockhazel Consulting Ltd | Information & communication | 2019 |
| Locuspace Ltd | Real estate | 2025 |
| Loggique Ltd | Wholesale & retail | 2021 |
| Lois Gunn Studio Limited | Wholesale & retail | 2025 |
| Lolabell Ltd | Wholesale & retail | 2016 |
| London Fields Publishing Limited | Information & communication | 2008 |
| Long Rambles Limited | Real estate | 2026 |
| Longbon & Co Ltd | Financial services | 2009 |
| Loopwhole Ltd | Information & communication | 2019 |
| Loublitz Ltd | Administrative & support | 2025 |
| Love a Taste Limited | Manufacturing | 2013 |
| Love Motorhomes Limited | Information & communication | 2010 |
| Lovemylaundry Ltd | Information & communication | 2019 |
| Lower Barn Baylham Management Company Limited | Households | 2021 |
| LRC Contracting Ltd | Construction | 2014 |
| Luckily Ltd | Extraterritorial | 2025 |
| Luckyturn Media Ltd | Information & communication | 2012 |
| Luke Biddulph Limited | Construction | 2018 |
| Lurvills Delight Limited | Manufacturing | 2015 |
| LUX Monitoring Limited | Administrative & support | 2011 |
| Luxmoore & Co Ltd | Manufacturing | 2011 |
| Luxury Tignes VAL D'Isere Ltd | Administrative & support | 2024 |
| M & C Engineering (Newbourne) Limited | Construction | 2002 |
| M & J Stone Developments Limited | Construction | 1985 |
| M J Spink Limited | Construction | 2002 |
| M Pawsey Ltd | Arts & recreation | 2025 |
| M. G. Whitby & Company Limited | Professional & scientific | 2002 |
| M. S. Goodhart Limited | Professional & scientific | 2015 |
| Maberley Properties Limited | Real estate | 2017 |
| Macinnes Tooling Limited | Wholesale & retail | 1992 |
| Madinina Consulting Limited | Information & communication | 2015 |
| Madrigal Yarns Ltd | Manufacturing | 2018 |
| Maggie & Friends Ltd | Wholesale & retail | 2026 |
| Maharishi Ayurveda Health Centre Rendlesham Ltd | Health & social care | 1992 |
| Maharishi Ayurveda Ltd | Wholesale & retail | 2020 |
| Maharishi Education Centre Limited | Hospitality | 1997 |
| Maharishi Garden Village Limited | Real estate | 2005 |
| Maharishi International Graduate School | Education | 2014 |
| Maharishi Limited | Education | 2004 |
| Make Fashion British Limited | Manufacturing | 2011 |
| Malins Associates Limited | Construction | 2011 |
| Mallard Close Meadows Management Company Limited | Households | 2019 |
| Mama on Call Limited | Information & communication | 2025 |
| Mann Energy Ltd | Financial services | 2025 |
| Mann Farms Limited | Agriculture & fishing | 1959 |
| Mann Renewables Ltd | Financial services | 2025 |
| Mansell Consultants Limited | Information & communication | 2007 |
| Marala Properties Ltd | Hospitality | 2006 |
| March Forth Consulting Ltd | Professional & scientific | 2024 |
| Marie Ellis Consulting Limited | Professional & scientific | 2018 |
| Mark Blackman Limited | Health & social care | 2024 |
| Mark Bowditch Ltd | Health & social care | 2009 |
| Mark Cutting Services Limited | Administrative & support | 2008 |
| Mark Palmer Portraiture Limited | Professional & scientific | 2000 |