| Hughes Properties Limited | Other services | 1959 |
| HWB Narberth Ltd | Hospitality | 2021 |
| Hydro Dynamic Pembrokeshire Limited | Arts & recreation | 2023 |
| I G Osteopathy Ltd | Health & social care | 2026 |
| I.D. Badham Limited | Professional & scientific | 2005 |
| I2R Services Ltd | Financial services | 2011 |
| Ice Candy Tenby Limited | Hospitality | 2022 |
| Iludo Limited | Arts & recreation | 2012 |
| ILUDO82 Limited | Arts & recreation | 2014 |
| Imaginediy Ltd | Wholesale & retail | 2015 |
| IN Search of Self Ltd | Other services | 2012 |
| Indie Burger Limited | Hospitality | 2016 |
| Innshore Holdings Ltd | Professional & scientific | 2023 |
| Innshore Limited | Hospitality | 2017 |
| Instelecs Ltd | Professional & scientific | 2016 |
| Internationally Spoilt | Manufacturing | 2011 |
| Irismead Limited | Wholesale & retail | 2003 |
| Islands View (Management) Penally Limited | Real estate | 2004 |
| Islay Court Management Company Limited | Households | 1994 |
| ITS Mykonos Tenby Ltd | Hospitality | 2026 |
| IWG Plant Hire & Groundworks Limited | Administrative & support | 2026 |
| J & R Properties (Tenby) Limited | Real estate | 1995 |
| J Davies Real Estate Ltd | Real estate | 2026 |
| J.J. Lewis Building Contractor Limited | Construction | 2002 |
| J3KG Electrical Ltd | Construction | 2022 |
| James-Goddard Accountancy Ltd | Professional & scientific | 2023 |
| Jane PR Catering Limited | Hospitality | 2023 |
| Jelifish Ltd | Information & communication | 2021 |
| Jemstone Construction Limited | Construction | 1997 |
| John Brebner Ingredients Ltd | Wholesale & retail | 2015 |
| Jones and Bradley Building Ltd | Construction | 2019 |
| JRE Parks Holdings Limited | Financial services | 2026 |
| Jrsw Services Ltd | Manufacturing | 2008 |
| JTL Cleaning Ltd | Administrative & support | 2025 |
| K.D. Designs Ltd. | Professional & scientific | 2002 |
| KD Developments Limited | Real estate | 2011 |
| KD Holiday Properties Limited | Hospitality | 2015 |
| Key ME UP Pete'Y Limited | Wholesale & retail | 2019 |
| L.G. Leisure (North Wales) Ltd | Arts & recreation | 2016 |
| Landway Property Limited | Construction | 2008 |
| Langdale Geoscience Ltd | Professional & scientific | 2022 |
| Laumayrose Limited | Hospitality | 2019 |
| LB Construction & Roofing Limited | Construction | 2023 |
| Leroychealhair Ltd | Other services | 2023 |
| Licensed Property of Wales Limited | | 1981 |
| Lion Hotel(Tenby),Limited | Hospitality | 1937 |
| Little Newton Ltd | Hospitality | 2019 |
| LK Holiday Park Limited | Hospitality | 2014 |
| Lockbox Group Limited | Construction | 2024 |
| Lollies Chocolate Emporium Limited | Wholesale & retail | 2023 |
| Lollies Traditional Sweet Shop Limited | Wholesale & retail | 2008 |
| Lucida Limited | Other services | 2024 |
| Luxeone Limited | Hospitality | 2018 |
| M W L Consultancy Services Limited | Professional & scientific | 2018 |
| Magler Technical Services Limited | Administrative & support | 2008 |
| Mahdi & Risalah 11 Ltd | Hospitality | 2022 |
| Makepeace Botanics Ltd | Manufacturing | 2024 |
| Makepeace Studio CIC | Health & social care | 2024 |
| Manorbier and District Community Transport Limited | Transport & logistics | 2005 |
| Marblehouse Limited | Construction | 2002 |
| Marcos Cars Ltd | Manufacturing | 2010 |
| Marcos Race Cars Ltd | Manufacturing | 2023 |
| Marcos Super Cars Ltd | Manufacturing | 2025 |
| Martins Corner Limited | Other services | 2016 |
| MAY Ideas Limited | Hospitality | 2023 |
| Maylaurose Limited | Construction | 2022 |
| Mayville Apartments Association Limited | Households | 2017 |
| MC492 Limited | Real estate | 2011 |
| Mehrez Limited | Hospitality | 2022 |
| Merrony Construction Limited | Construction | 2014 |
| Middle Meadow Developments Limited | Construction | 2019 |
| Millie Marotta Limited | Arts & recreation | 2015 |
| Milton Fish & Chip Shop Ltd | Hospitality | 2021 |
| Milton Sandwich Bar Ltd | Hospitality | 2025 |
| Mirrormore Ltd | Manufacturing | 2026 |
| Mobi Group Limited | Construction | 2024 |
| Mopani Properties Limited | Real estate | 2017 |
| MOR Media (Pembs) Ltd | Professional & scientific | 2023 |
| MOR Tenby Limited | Wholesale & retail | 2019 |
| More Security Training Ltd | Education | 2025 |
| Morgan & Company 1996 Limited | Professional & scientific | 2024 |
| Morris Bros.(Tenby Properties)Limited | Real estate | 1964 |
| Morris Bros.(Tenby)Limited | Wholesale & retail | 1964 |
| Mountain View Camping & Glamping Ltd | Hospitality | 2026 |
| MR Chips (Pembroke Dock) Limited | Hospitality | 2003 |
| MT & AL Property Limited | Real estate | 2024 |
| N&B Pembs Ltd | Financial services | 2026 |
| Natural Leaders Club Limited | Education | 2023 |
| Naturally Gifted Tenby Ltd | Wholesale & retail | 2023 |
| New ST Agathas Tenby Management Company Limited | Households | 2015 |
| Newton Heights Limited | Households | 2016 |
| NJA Consultants Ltd | Professional & scientific | 2022 |
| Nltk Holdings Limited | Financial services | 2005 |
| Norman Hughes Design Limited | Real estate | 1946 |
| North Beach Pizzeria Limited | Hospitality | 2012 |
| North Beach View Limited | Households | 1989 |
| NRT Consultancy (Pembs) Ltd | Professional & scientific | 2018 |
| NTH Layer Ltd | Information & communication | 2026 |
| Oaktree Court Management Company (Kilgetty) Limited | Households | 1990 |
| Old Vicarage Properties Limited | Real estate | 2008 |