| A1 Unity Group Ltd | Croydon | 2024 |
| A1 UOK Ltd | Chislehurst | 2022 |
| A1 Utilities Limited | North Yorkshire | 2005 |
| A1 Waste Solutions Limited | Enfield | 2015 |
| A1 Welding Solutions Ltd | London | 2018 |
| A1&PM Mind Capital Limited | London | 2026 |
| A1-JETCONSULTING Limited | Weymouth | 2022 |
| A1-TEN Company Ltd | Glasgow | 2015 |
| A10 Architects Limited | Glenrothes | 2010 |
| A10 BOB Ltd | London | 2025 |
| A10 Consultancy Ltd | Basingstoke | 2019 |
| A10 Digital Limited | Rugby | 2024 |
| A10 Mechanical Services Ltd | Newcastle Upon Tyne | 2024 |
| A10 Motors Ltd | Peterborough | 2015 |
| A10 Networks Limited | London | 2010 |
| A105 Productions Ltd | Bishop'S Stortford | 2025 |
| A11.2 Design Limited | London | 2025 |
| A11D Ltd | Glasgow | 2026 |
| A12 Design Ltd | Hornchurch | 2025 |
| A121 Training Ltd | Driffield | 2021 |
| A12A Global Ltd | Bristol | 2015 |
| A13R Limited | London | 2025 |
| A16 Holdings Limited | Faversham | 2024 |
| A17 Limited | Bourne End | 2024 |
| A18 Group Limited | London | 2018 |
| A1802 Ltd | London | 2023 |
| A184 Limited | Newcastle Upon Tyne | 2018 |
| A19 Consultancy Limited | York | 2022 |
| A1A Bookkeeping Services Stoke Ltd | Stoke-On-Trent | 2021 |
| A1A Ltd | Flockton | 2011 |
| A1C Technik Ltd | Broughton-In-Furness | 2011 |
| A1CAD Ltd | Stone | 2025 |
| A1DAY Limited | Oxfordshire | 2025 |
| A1GXP Ltd | London | 2022 |
| A1MARQUEE Hires Limited | Hounslow | 2022 |
| A1R Consultancy Limited | Hertford | 2017 |
| A1RAF Limited | Chessington | 2018 |
| A1SAFESITE Ltd | Hartlepool | 2023 |
| A1SRJ Limited | London | 2026 |
| A1T1 Ltd | London | 2020 |
| A1TANG Limited | Altrincham | 2018 |
| A1TEC Solutions Ltd | Edgware | 2023 |
| A1TELECOMMS Ltd | Cheltenham | 2024 |
| A1VL Limited | London | 2021 |
| A1W Ltd | London | 2026 |
| A2 - Architecture & Development Ltd | Fareham | 2020 |
| A2 Advanced Monitoring Limited | Hadleigh, Benfleet | 2023 |
| A2 and B Limited | Aberdeen | 2023 |
| A2 Certified Accountants Limited | Abbots Langley | 2023 |
| A2 Consultants Quality, Compliance and ISO Systems Limited | Cheltenham | 2025 |
| A2 Creative Limited | Whitley Bay | 2004 |
| A2 Data Consultants Ltd | Waltham Cross | 2026 |
| A2 Design Shed Ltd | Milton Keynes | 2023 |
| A2 H&S Ltd | Bathgate | 2025 |
| A2 Innovations Ltd | Milton Keynes | 2020 |
| A2 Ivest Limited | Middlesex | 2020 |
| A2 Management Ltd | London | 2025 |
| A2 Maritime Ltd | Hadleigh, Benfleet | 2023 |
| A2 Partners Accountancy Ltd | London | 2024 |
| A2 Plumbers Ltd | London | 2013 |
| A2 Site Investigation Limited | Hadleigh, Benfleet | 2020 |
| A2 Studio Design Ltd | Huddersfield | 2026 |
| A2 Studio Limited | London | 2006 |
| A2 Website Designs Ltd | Gravesend | 2020 |
| A2/SW/HK Limited | London | 2005 |
| A2024CONSULTING Limited | Manchester | 2024 |
| A21 Business Services Limited | Tunbridge Wells | 2024 |
| A21 Events UK Ltd | London | 2009 |
| A21ARCHITECTS Ltd | London | 2011 |
| A22 Consulting Ltd | Lanark | 2025 |
| A24 Consulting Ltd | London | 2023 |
| A24 Management Limited | Sheerness | 2024 |
| A24 Operations Limited | London | 2018 |
| A24 Strategic Partners Limited | London | 2025 |
| A26&DIA Design Studio GB Ltd | Guildford | 2024 |
| A29 Archaeology Ltd | Oxford | 2025 |
| A2A Advertising Limited | Cumbria | 2003 |
| A2A Business Ltd | Hornchurch | 2004 |
| A2A Business Solutions Limited | Cramlington | 2019 |
| A2A Consulting Limited | Weymouth | 2015 |
| A2A Heat Pumps Limited | Watford | 2020 |
| A2ACH Limited | Edinburgh | 2026 |
| A2B Access and Inspection Ltd | Glasgow | 2018 |
| A2B Accounting Limited | Hazlerigg | 2021 |
| A2B Advisory Consulting Limited | Wilmslow | 2016 |
| A2B Business Consulting Ltd | Burntwood | 2020 |
| A2B Business Growth Ltd | Chester | 2017 |
| A2B Capital Holdings Limited | Gateshead | 2024 |
| A2B Construction Solutions Limited | Nottingham | 2015 |
| A2B Consultancy Limited | Hoddesdon | 2012 |
| A2B Consultancy Services Limited | Slough | 2015 |
| A2B Creative Limited | London | 2012 |
| A2B Design (Bridlington) Limited | Bridlington | 2021 |
| A2B Express Travel Limited | Eastleigh | 2003 |
| A2B Freight Logistics Limited | Solihull | 2022 |
| A2B Global Mindset Ltd | Grundisburgh | 2020 |
| A2B HV Cabling Assistance Ltd | Preston | 2016 |
| A2B LAB Supplies Ltd | Manchester | 2021 |
| A2B Lighting Design Ltd | Nuneaton | 2018 |
| A2B Ltd | Colchester | 2015 |