| Air Compressor Ltd | Weston-Super-Mare | 2022 |
| Air Compressor Systems Limited | Seaton | 1998 |
| Air Conditioning and Refrigeration Industry Board | Carshalton | 1995 |
| Air Conditioning Inspection Solutions Ltd | Bradford | 2016 |
| Air Consulting Associates Limited | London | 2019 |
| Air Consulting Global Limited | Lisburn | 2014 |
| Air Consulting Limited | Aldershot | 2018 |
| Air Control Industries EOT Trustee Limited | Axminster | 2022 |
| Air Convenience Ltd | London | 2026 |
| Air Cover PR Limited | Farnham | 2020 |
| Air Craft (Southern) Ltd | Southampton | 2010 |
| Air Creative Marketing Limited | Stockbridge | 2004 |
| Air Cushion Vehicle System Ltd | Salford Manchester | 2005 |
| Air Design Limited | London | 1998 |
| Air Devices Ltd | Devon | 2001 |
| Air Diffusion Limited | Wednesbury | 1973 |
| Air Digital Technology Ltd | London | 2024 |
| Air Domain Solutions Ltd | Weymouth | 2013 |
| Air Drone Surveying Ltd | St. Leonards-On-Sea | 2021 |
| Air Ducters Limited | Birmingham | 2018 |
| Air Ducts (Southern) Plastics Limited | Aldershot | 2006 |
| Air Dust Odour Ltd | Houghton Le Spring | 2025 |
| Air Energi Group Limited | Manchester | 2005 |
| Air Energy (NI) Ltd | Belfast | 2007 |
| Air England Limited | Horsham | 1994 |
| Air Exhibition Ltd | Addlestone | 2023 |
| Air EYE Advantage Ltd | Lyme Regis | 2025 |
| Air FD Limited | Stirling | 2019 |
| Air Filtration Consultants Limited | Airdrie | 2023 |
| Air Florida Inc | London | 1982 |
| Air Force Projects Ltd | London | 2024 |
| Air Fuaradh Limited | Glasgow | 2025 |
| Air GAP Network Security Solutions Ltd | London | 2020 |
| Air GB Engineering Ltd | Derby | 2017 |
| Air Giants Limited | Bristol | 2020 |
| Air Heating (Southern) Limited | Basildon | 2016 |
| Air Holdco Limited | Near Stanley | 2020 |
| Air Hound Ltd. | Chester Le Street | 2017 |
| Air House Limited | London | 2019 |
| Air Hydro Tech Limited | London | 2011 |
| Air Images Limited | Northumberland | 2002 |
| Air Industrial Equipment Company Ltd. | Waltham Abbey | 2011 |
| Air Innovation Consultants Limited | London | 2007 |
| Air Integrity Solutions Limited | Durham | 2025 |
| Air International Thermal (United Kingdom) Limited | London | 2017 |
| Air IP Limited | Gainsborough | 2024 |
| Air Kopter Engineering Limited | Aberdeen | 2022 |
| Air Land & Subsea Inspection Technologies Ltd | Glasgow | 2014 |
| Air Land Integration Ltd | Dursley | 2011 |
| Air Land Sea Safety Solutions Ltd | Belfast | 2021 |
| Air Land Technology Limited | Grangetown, | 2012 |
| Air Law Limited | Westerham | 2023 |
| Air Law Options Limited | Buntingford | 2003 |
| Air Leakage Testing Limited | Aylesbury | 2002 |
| Air Leasing Limited | Sywell | 1992 |
| Air Logistics Group Limited | Castle Donington | 2001 |
| Air Management Solutions (AMS) Ltd | Hook | 2019 |
| Air Marketing Group Limited | Exeter | 2016 |
| Air Marketing Limited | Exeter | 2019 |
| Air Marketing Services Limited | London | 1986 |
| Air Mobility Solutions Ltd | Sunbury-On-Thames | 2022 |
| Air Movement Ltd | Manchester | 2020 |
| Air Movement Systems Ltd | Loughborough | 2006 |
| Air N.I Ltd | Lisburn | 2022 |
| Air Odyssea Limited | High Wycombe | 2024 |
| Air Outdoor Media Ltd | London | 2010 |
| Air Outsourcing Ltd | Streatham | 2023 |
| Air Partner Group Limited | Gatwick | 1998 |
| Air Passenger Solicitors Limited | Horsham | 2019 |
| Air Pathology Ltd | Sevenoaks | 2017 |
| Air Payroll Services Limited | Milton Keynes | 2020 |
| Air Permeability Testing UK Ltd | Shrewsbury | 2017 |
| Air Phoenix Digital Limited | West Horndon | 2021 |
| Air Photo Services Limited | Swindon | 2004 |
| Air Plants Group Limited | Leicester | 1930 |
| Air Plants Heating Limited | Leicester | 1996 |
| Air Plants Limited | Leicester | 1980 |
| Air Power Green Energy Technologies Limited | Derby | 2009 |
| Air Power Green Town Technologies Limited | Derby | 2009 |
| Air Pressure Testing Ltd | Stratford-Upon-Avon | 2004 |
| Air Productions Ltd | London | 2018 |
| Air Products Group Limited | Chertsey | 1995 |
| Air Pure Services Ltd | Glossop | 2023 |
| Air Purification Skroll Limited | Gateshead | 2017 |
| Air Purifiers Limited | United Kingdom | 2021 |
| Air Purity Ltd | Saffron Walden | 2020 |
| Air Quality & Safety Consulting Ltd | Edinburgh | 2019 |
| Air Quality Analysers Ltd | London | 2024 |
| Air Quality Assessment & Policy Limited | Pinner | 2014 |
| Air Quality Assessments Ltd | Burnham-On-Sea | 2014 |
| Air Quality Consultants Limited | Bristol | 1993 |
| Air Quality Experts Ltd | Brighton | 2024 |
| Air Quality Limited | Rochester | 2015 |
| Air Quality Measurements Limited | Horsham | 2002 |
| Air Quality Plan Ltd | Fareham | 2013 |
| Air Quality Research Ltd | Chester | 2008 |
| Air Quality Solutions Ltd | Nottingham | 2022 |
| Air Race CC Ltd | Waltham Abbey | 2013 |
| Air Rentals Limited | Stockport | 1976 |
| Air Reports Ltd | West Wickham | 2015 |