| Aged to Perfection Upholstery Limited | Manufacturing | 2013 |
| Agenda Solutions Holdings Limited | Professional & scientific | 2009 |
| Agenzia 14 (International) Limited | Wholesale & retail | 2004 |
| Agenzia 14 Limited | Wholesale & retail | 2009 |
| AGJ Boba Limited | Hospitality | 2023 |
| Agjd Holdings Ltd | Administrative & support | 2024 |
| AGM Sofas Limited | Wholesale & retail | 2025 |
| AH & Co Holdings Limited | Professional & scientific | 2009 |
| AH Energy Services Limited | Administrative & support | 2019 |
| AHL Construction & Development Ltd | Construction | 2021 |
| Ahmed Joinery Limited | Construction | 2025 |
| Ahod Windows Ltd | Construction | 2026 |
| Ahra Properties Ltd | Real estate | 2025 |
| AHY Carpets Ltd | Wholesale & retail | 2023 |
| AHY Homes Ltd | Real estate | 2025 |
| AI Deals Ltd | Wholesale & retail | 2025 |
| AI Insulation Limited | Construction | 2018 |
| Aiden Fast Food Ltd | Hospitality | 2025 |
| Aidezel Ltd | Wholesale & retail | 2025 |
| AIM 2 Change CIC | Education | 2024 |
| AIM Applications Holdings Limited | Financial services | 2018 |
| AIM Applications Limited | Manufacturing | 2007 |
| AIM Education Ltd | Education | 2022 |
| Air & Ventilation Testing UK Ltd | Professional & scientific | 2025 |
| Airos Tech Ltd | Information & communication | 2025 |
| Airtab Limited | Extraterritorial | 2011 |
| AIW Real Estate Ltd | Real estate | 2024 |
| AJ Khan Ltd | Real estate | 2020 |
| AJ Macdonald Copywriting Limited | Professional & scientific | 2024 |
| AJ Sales Consulting Ltd | Other services | 2016 |
| AJ Scaffolds Ltd | Construction | 2026 |
| AJ Tour Services Ltd | Administrative & support | 2025 |
| AJ Trade & Logistics Ltd | Wholesale & retail | 2022 |
| AJA Maintenance Specialists Ltd | Construction | 2018 |
| AJB Water Solutions Ltd | Professional & scientific | 2021 |
| Ajem Trading Limited | Wholesale & retail | 2020 |
| AJK Real Estate Ltd | Real estate | 2013 |
| AK Globe Trades Ltd | Financial services | 2025 |
| AK Motors (Burnley) Limited | Wholesale & retail | 2025 |
| AK Property NW Ltd | Real estate | 2021 |
| AK Taxi Solution Ltd | Wholesale & retail | 2024 |
| AK Trading Northwest Ltd | Wholesale & retail | 2020 |
| AKA Building Services Ltd | Construction | 2021 |
| Akash Burnley Ltd | Hospitality | 2025 |
| AKF Ltd | Real estate | 2022 |
| AKHT103 Solutions Limited | Health & social care | 2012 |
| Akhtar Regenerative Ltd | Health & social care | 2024 |
| AKL59 Ltd | Real estate | 2021 |
| Akorn Financial Advice Limited | Professional & scientific | 2014 |
| Akshi Super Store Ltd | Wholesale & retail | 2025 |
| Aky’S Logistics Ltd | Transport & logistics | 2021 |
| AL AUF Holdings Ltd | Real estate | 2019 |
| AL Kaatib Limited | Professional & scientific | 2023 |
| AL Qaim Travel Limited | Administrative & support | 2025 |
| AL Retailers Limited | Wholesale & retail | 2025 |
| Al-Asr Education Centre | Education | 2000 |
| Al-Hadi Fruit and Meat Limited | Wholesale & retail | 2025 |
| Aladdins Cave Burnley Limited | Wholesale & retail | 2020 |
| Aladdins Fonez Limited | Wholesale & retail | 2017 |
| Albino Recordings (UK) LLP | | 2007 |
| Albrentia Limited | Professional & scientific | 2015 |
| Albury Fires Limited | Manufacturing | 2006 |
| Alcohol and Drug Abstinence Service (Management) Limited | Extraterritorial | 2008 |
| Aldenham Homes Ltd | Real estate | 2017 |
| Alderson Homes Ltd | Construction | 2023 |
| Alex GAS and Heating Ltd | Construction | 2022 |
| Alex Neill Class Representative Limited | Other services | 2022 |
| Alexa Nail & Beauty Bar Limited | Other services | 2020 |
| Alexander Joinery Ltd | Construction | 2019 |
| Alfa Education Limited | Education | 2014 |
| Alfar Properties Ltd | Real estate | 2024 |
| ALG Logistics Limited | Transport & logistics | 2013 |
| Alif Food Limited | Hospitality | 2025 |
| Alison Chew Property Limited | Real estate | 2017 |
| ALL Fresh Fruit & VEG Ltd | Wholesale & retail | 2012 |
| ALL in Blends Ltd | Wholesale & retail | 2025 |
| ALL Season Care Ltd | Health & social care | 2022 |
| ALL Seasons Grounds & Landscaping Contractors Ltd | Administrative & support | 2021 |
| ALL Stores Clothing Limited | Wholesale & retail | 2006 |
| ALL Things Inflatable Ltd | Administrative & support | 2024 |
| ALL4BIRTH CIC | Information & communication | 2021 |
| ALL4HOLDINGS Limited | Financial services | 2017 |
| Allen Automation & Controls (AAC) Limited | Professional & scientific | 2014 |
| Allen Commercial Interiors Ltd | Construction | 2009 |
| Allendale Property Ltd | Real estate | 2021 |
| ALLERTON18 Ltd | Professional & scientific | 2023 |
| Alliance Brothers Foods Limited | Wholesale & retail | 2023 |
| Allied Billiards (Northern) Limited | Hospitality | 1998 |
| Allied Pipefreezing Services Limited | Administrative & support | 2000 |
| Allied Pipeline Services Ltd | Administrative & support | 2010 |
| Alma Transport Ltd | Transport & logistics | 2024 |
| Almond Gibson Ltd | Hospitality | 2018 |
| ALP Softies Ltd | Wholesale & retail | 2024 |
| Alpha Housing Developments Limited | Real estate | 2022 |
| Alpha Property NW Ltd | Real estate | 2025 |
| Alpine Trucking Ltd | Transport & logistics | 1999 |
| Alraf Ltd | Wholesale & retail | 2023 |
| Alrafi Limited | Construction | 2016 |
| Alteris Software Consultancy Ltd | Information & communication | 2021 |
| Alternative Football CIC | Education | 2022 |