| Aila RDC Emea Chapter Limited | Southwark | 2017 |
| Aila's Nails & Spa Limited | Belfast | 2022 |
| Ailec Holdings Limited | Cornwall | 1982 |
| Ailes Lash Limited | Sidcup | 2019 |
| Ailia Ltd | Milton Keynes | 2017 |
| Ailiaglobal Ltd | London | 2026 |
| Ailie Corporation Limited | Huntingdon | 2016 |
| Ailo Limited | Sutton | 2024 |
| Ailo Studios Ltd | Plymouth | 2026 |
| Ailogica Limited | Altrincham | 2016 |
| Ailsa Jane Aesthetics Ltd | Wantage | 2022 |
| Ailspin Properties Limited | Arbroath | 2008 |
| AIM (London) Ltd | Taplow | 2016 |
| AIM 27 Ltd | Egham | 2024 |
| AIM Audio Visual Ltd | Farnham | 2017 |
| AIM Collaborations Limited | Macclesfield | 2024 |
| AIM Electrical Solutions Ltd | Louth | 2023 |
| AIM Exports Limited | Leicester | 2006 |
| AIM for Elegance Limited | Halstead | 2024 |
| AIM for Excellence Sporting Ltd | London | 2026 |
| AIM Fundraising Consultancy Ltd | South Croydon | 2020 |
| AIM GRP UK Ltd | Gravesend | 2009 |
| AIM HI Transport Ltd | Cannock | 1998 |
| AIM High Photography Ltd | Andover | 2008 |
| AIM Higher Canine Services Limited | Poole | 2021 |
| AIM Internet Limited | Birmingham | 1998 |
| AIM Leisure Limited | Macclesfield | 2018 |
| AIM Medical Aesthetics Ltd | Oswestry | 2024 |
| AIM Renewables Ltd | Bathgate | 2021 |
| AIM Search & Selection Limited | Rochford | 2022 |
| AIM Shetland Ltd | Shetland | 2023 |
| AIM Stitches Limited | Newmarket | 2018 |
| AIM to Sustain Limited | Shrewsbury | 2023 |
| AIM Trade Limited | Hornchurch | 2010 |
| AIM Welding Limited | Inverness | 2017 |
| Aimalohi Limited | Peterborough | 2021 |
| Aiman Chowchara for Trading and Investment Ltd | London | 2024 |
| Aiman Software Ltd | London | 2025 |
| Aimanzain Global Consultant Ltd | Birmingham | 2025 |
| Aimcauk | Nantwich | 2018 |
| Aimdriod Limited | Kilmarnock | 2010 |
| Aimee Brown Hairdressing Ltd | Darlington | 2019 |
| Aimee Dunne Ltd | Bromley | 2012 |
| Aimee Leigh Hair Ltd | Grimsby | 2024 |
| Aimee M Coaching Ltd | Bolton | 2026 |
| Aimee Marie Hair & Aesthetics Ltd | Derby | 2021 |
| Aimee Ryan Limited | Glasgow | 2022 |
| Aimee Smith Permanent Cosmetics Limited | Nottingham | 2017 |
| Aimee's Hair & Beauty Ltd | Bournemouth | 2011 |
| Aimee's Hair Limited | Spalding | 2025 |
| Aimen’S Barbers Limited | Normanton | 2025 |
| Aimes Health and Beauty Limited | Knaresborough | 2012 |
| Aimex Focus Limited | London | 2009 |
| Aimgo Limited | Newcastle Upon Tyne | 1989 |
| Aimii Limited | Manchester | 2010 |
| Aimm Consultancy Ltd | Hove | 2023 |
| Aims Beauty Ltd | Hayes | 2025 |
| Aimse Europe Limited | Colchester | 2013 |
| Aimsoo Brows Limited | Kilmarnock | 2022 |
| AIMSTECH786 Ltd | Thornton Heath | 2020 |
| Aimtodeliver Limited | London | 2012 |
| Aimtoheal Limited | Pinner | 2025 |
| Aimy Beauty Ltd | Basingstoke | 2023 |
| Aimée B Beauty Aesthetics Limited | Altrincham | 2019 |
| Aina Couture Ltd | Birmingham | 2025 |
| Aina Trilogy Foundation | Gillingham | 2018 |
| Aine the Upholsterer Ltd | London | 2023 |
| Ainger Consultancy Ltd | Towcester | 2023 |
| Ains Beauty Salon Limited | Reigate | 2024 |
| Ainsdale Beauty Ltd | Ormskirk | 2017 |
| Ainsdalehair Limited | Southport | 2012 |
| Ainsley Keller Coaching Ltd | London | 2023 |
| Ainslie Contracting Limited | Galashiels | 2008 |
| Ainslie Currie Limited | Glasgow | 2011 |
| Ainsworth Hurst Limited | Riversway | 1988 |
| Aintree GIN Ltd | Liverpool | 2019 |
| AIO Create Ltd | London | 2024 |
| AIO Vision Ltd | Market Harborough | 2015 |
| Aiof II European Debt Holdings Limited | London | 2023 |
| Aion Aesthetics Ltd | Arlesey | 2023 |
| Aion Design Ltd | Soughton | 2018 |
| Aion Partners Limited | Warwick | 2019 |
| Aionia Limited | Birmingham | 2013 |
| Aionios Investments Ltd | Ongar | 2024 |
| Aionix Limited | Bury St. Edmunds | 2024 |
| Aiph UK Limited | Didcot | 2019 |
| AIQ Synertial Ltd | London | 2018 |
| Aiquin Nails Limited | Newcastle Upon Tyne | 2019 |
| Air & Beyond Metals Limited | London | 2023 |
| Air & Sea Analytics Ltd | London | 2019 |
| Air 2 Root Turfcare Limited | Bromsgrove | 2019 |
| Air Aesthetics Clinic ST Albans Ltd | Bromsgrove | 2022 |
| Air Aesthetics Ltd | Henley-In-Arden | 2011 |
| Air Atlanta Aviaservices Limited | Crawley | 1998 |
| Air B & Clean Limited | Ventnor | 2022 |
| Air Cargo Booking Ltd | London | 2018 |
| Air Claims Guru Ltd | London | 2023 |
| Air Compressors & Tools Ltd | Warrington | 1920 |
| Air CON Air Source Refrigeration Ltd | Bristol | 2018 |
| Air Conditioning and Related Environmental Services Limited | Southend On Sea | 2008 |