| Kcphysio 1 UK Ltd | Administrative & support | 2017 |
| KEN Brooker Creative Ltd | Professional & scientific | 2020 |
| KEN Russell Farms Ltd | Agriculture & fishing | 2015 |
| Kenilprop RTM Co Ltd | Real estate | 2015 |
| Kepplestone (Eastbourne) Limited | Households | 1987 |
| Keval Business Services Limited | Administrative & support | 2016 |
| Key Skills Consultancy Ltd | Professional & scientific | 2020 |
| Keystone Family Advisers Ltd | Professional & scientific | 2014 |
| KGC Air Conditioning Ltd | Construction | 2022 |
| KI London Ltd | Manufacturing | 2017 |
| Kierz Brickwork Ltd | Construction | 2025 |
| Kindred Community Ltd | Professional & scientific | 2020 |
| Kindred Concepts Limited | Extraterritorial | 2025 |
| King Ecom Ltd | Wholesale & retail | 2013 |
| Kingsley Risk Management Limited | Professional & scientific | 2018 |
| Kingsrock Construction Ltd | Construction | 2021 |
| Kingsrock Group Ltd | Administrative & support | 2024 |
| Kingsrock Ltd | Professional & scientific | 2018 |
| Kippson Limited | Wholesale & retail | 2015 |
| KJA Strategy Limited | Professional & scientific | 2018 |
| Kl&Co. Ltd | Construction | 2015 |
| KMG Design Ltd | Construction | 2012 |
| KONAN20 Limited | Professional & scientific | 2025 |
| Kooyman Limited | Health & social care | 2004 |
| KPK Limited | Wholesale & retail | 2013 |
| Kr-Infra Limited | Real estate | 2024 |
| Kr-Infra-It Limited | Information & communication | 2024 |
| Kraftopia Ltd | Manufacturing | 2022 |
| KRT Accountants Limited | Professional & scientific | 2016 |
| KVJ Ltd | Wholesale & retail | 2019 |
| L & C DIY Group Ltd | Wholesale & retail | 2024 |
| L & J Properties Limited | Real estate | 2002 |
| L MAN Ltd. | Professional & scientific | 2014 |
| L&N Consultants Ltd | Professional & scientific | 2024 |
| L&N Distribution Ltd | Transport & logistics | 2024 |
| Lakeside Investments Ltd | Real estate | 2006 |
| Lame Games Limited | Manufacturing | 2017 |
| Langney Car Wash Ltd | Administrative & support | 2025 |
| Lanhorz Ltd | Information & communication | 2026 |
| LAS Production Studio Ltd | Information & communication | 2019 |
| Laserworks Limited | Other services | 2024 |
| Latitude Films Limited | Information & communication | 2001 |
| Latitude Software Design Limited | Information & communication | 1997 |
| Lawrence Paraplanning 2 Ltd | Professional & scientific | 2022 |
| Lawrence Paraplanning Ltd | Professional & scientific | 2015 |
| LB Accounts Ltd | Professional & scientific | 2021 |
| Leadbetter & Good Ltd | Wholesale & retail | 2012 |
| Leak Detection Services South East Ltd | Construction | 2025 |
| Learn Digital Ltd | Information & communication | 2018 |
| Lebrel Worldwide Limited | Professional & scientific | 2025 |
| LEE Bolingbroke Racing Ltd | Arts & recreation | 2007 |
| LEE Refrigeration Services Limited | Manufacturing | 2002 |
| Leemans Ltd | Real estate | 2018 |
| LET US Figure IT OUT Ltd | Professional & scientific | 2023 |
| Levelplane Limited | Real estate | 2006 |
| Lewhar Limited | Professional & scientific | 2019 |
| LEX DE Ltd | Wholesale & retail | 2014 |
| LF Holdco 2 Ltd | Financial services | 2024 |
| Liam Corporation Ltd | Wholesale & retail | 2017 |
| Libra Balance Limited | Health & social care | 2016 |
| Light My Fire Stove Installations Ltd | Construction | 2025 |
| Lighthutt Limited | Professional & scientific | 2012 |
| Lime Letter Language Services Ltd. | Professional & scientific | 2013 |
| Limes (Eastbourne) Limited(The) | Households | 1960 |
| Limetree Services Southern Ltd | Agriculture & fishing | 2024 |
| Limitless Digital Media Limited | Professional & scientific | 2019 |
| Lincoln's Eastbourne Limited | Hospitality | 2021 |
| Linda’S Bakes Ltd | Hospitality | 2020 |
| Linmore Tech Limited | Construction | 2026 |
| Liquid Solutions UK Limited | Wholesale & retail | 2004 |
| Little Bears Creative Play Sessions CIC | Education | 2017 |
| LIZ Dowling Marketing Ltd | Professional & scientific | 2024 |
| LIZ Laine Reps UK Ltd | Information & communication | 2025 |
| LJE Property Ltd | Real estate | 2024 |
| Local Commercial Limited | Real estate | 2017 |
| Local Residential Ltd | Real estate | 2025 |
| Loki Estates Ltd | Real estate | 2016 |
| London Mexico Limited | Administrative & support | 2017 |
| Long Dog Holdings Limited | Financial services | 2024 |
| Long MAN Brewery Limited | Manufacturing | 2011 |
| Longhouse Lettings Ltd | Real estate | 2020 |
| Loud Riders Ltd | Wholesale & retail | 2017 |
| Love Canvas Ltd | Wholesale & retail | 2020 |
| Lovely Holdings Ltd | Real estate | 2019 |
| Lovely Pubs Ltd | Hospitality | 2004 |
| LOW Impact Limited | Construction | 2010 |
| Lsks Properties Ltd | Real estate | 2025 |
| Lsrs Properties Ltd | Construction | 2025 |
| Ltpcompany Limited | Wholesale & retail | 2023 |
| Lubro Ltd | Wholesale & retail | 2026 |
| Lucky Ticket Competitions Ltd | Extraterritorial | 2021 |
| Luke Madhanga Consulting Limited | Information & communication | 2019 |
| Lumora Skin LLP | | 2019 |
| Lunatic Surf WAX Ltd | Manufacturing | 2026 |
| Lynholm Road Polegate Freehold Ltd | Real estate | 2003 |
| Lynx RM Limited | Information & communication | 2013 |
| M and P Removals Ltd | Transport & logistics | 2023 |
| M B Cable Limited | Construction | 2009 |
| M W Pyle Roofing Contracts Division Limited | Construction | 2003 |
| M&M Developments South East Ltd | Real estate | 2025 |