| Assert Ltd | Brentwood | 2006 |
| Asserta Limited | Barnet | 2005 |
| Assertis Limited | Maidstone | 2000 |
| Assertive Infosec Solutions Limited | Camberley | 2026 |
| Assertive Media Solutions Ltd | Milton Keynes | 2012 |
| Assertthat Limited | Chester | 2019 |
| Assess ALL Areas Ltd | Brighton | 2019 |
| Assess on Demand Limited | Harrogate | 2023 |
| Assess the Renter Ltd | London | 2025 |
| Assess Viva Ltd | Alexandria | 2025 |
| Assessable Technology Limited | Middlesbrough | 2024 |
| Assessely Ltd | Congleton | 2024 |
| Assessfirst UK Ltd | London | 2022 |
| Assessify Health Ltd | Wembley | 2026 |
| Assessio Learning Limited | Newry | 2024 |
| Assessity Ltd | Coventry | 2020 |
| Assesslens Limited | Northwood | 2024 |
| Assessme Ltd | Cheltenham | 2010 |
| ASSESSME911 Ltd | London | 2025 |
| Assessment Direct Limited | Gloucestershire | 2001 |
| Assessment First Ltd | Torpoint | 2026 |
| Assessment Intelligence Limited | Bideford | 2020 |
| Assessment Legal Limited | Oakham | 2017 |
| Assessment Technologies Limited | Oxford | 2020 |
| ASSESSMENT21 Limited | Whaley Bridge | 2006 |
| Assessmentday Ltd | Chelmsford | 2010 |
| Assessmytax Ltd | Chelmsford | 2026 |
| Asset 360 Ltd | Wrexham | 2023 |
| Asset Acquisition Capital Limited | Gloucester | 2022 |
| Asset Arts Production Services Ltd | Wokingham | 2019 |
| Asset Base London Limited | London | 2014 |
| Asset Buccaneer Limited | Wymondham | 2014 |
| Asset Business Systems Limited | Bristol | 1997 |
| Asset Care Plus Ltd | Ipswich | 2025 |
| Asset Centrix Ltd | Uxbridge | 2025 |
| Asset Chain Ltd | Prestonpans | 2018 |
| Asset Clearing Network Ltd | Henley-On-Thames | 2026 |
| Asset Clinical Improvement CIC | London | 2026 |
| Asset Cloud Limited | London | 2024 |
| Asset Control Technology Limited | London | 1998 |
| Asset Control Topco Limited | London | 2018 |
| Asset Curve Ltd | London | 2021 |
| Asset Data Management Ltd | Weston-Super-Mare | 2025 |
| Asset Data Solutions Ltd | Newton Abbot | 2024 |
| Asset Drive AI Ltd | Bourne End | 2026 |
| Asset Family Limited | Bristol | 2025 |
| Asset Films Ltd | Eastbourne | 2012 |
| Asset Finance International Limited | London | 2009 |
| Asset Finance Technology Limited | Glasgow | 2023 |
| Asset FLO Limited | Godalming | 2025 |
| Asset Flow Ltd | Southend | 2020 |
| Asset Funding Ltd | Selkirk | 2017 |
| Asset Go Solutions Ltd | Sheffield | 2020 |
| Asset Guard Group Ltd | Caterham | 2025 |
| Asset Guardian Solutions Limited | Wishaw | 2010 |
| Asset Hound Limited | Harrogate | 2026 |
| Asset ICT Ltd | London | 2000 |
| Asset ID Ltd | London | 2004 |
| Asset Information Solutions Ltd | Canterbury | 2014 |
| Asset Infotech Limited | Slough | 2012 |
| Asset Inheritance Ltd | Uxbridge | 2025 |
| Asset Insights Limited | Lichfield | 2018 |
| Asset Integrated Systems Ltd | Newry | 2020 |
| Asset Intelligence Holdings Limited | Nottingham | 2024 |
| Asset Iris Ltd | Hemel Hempstead | 2026 |
| Asset Logic Systems Ltd | High Wycombe | 2024 |
| Asset Management Advisors Limited | Bognor Regis | 2014 |
| Asset Management International Group Ltd | Chertsey | 2025 |
| Asset Maps Ltd | London | 2024 |
| Asset Monitoring Solution Group (UK) Limited | Hungerford | 2009 |
| Asset One (Digital) Limited | Aberdeen | 2025 |
| Asset Performance Consultants Limited | Rotherham | 2020 |
| Asset Plan Ltd | Leicester | 2012 |
| Asset Plus Digital Limited | Lincoln | 2025 |
| Asset Plus Ltd | Harrow | 1995 |
| Asset Project Solutions Ltd | Larbert | 2010 |
| Asset Protect Ltd | Altrincham | 2023 |
| Asset Recycling Ltd | Glasgow | 2019 |
| Asset Registrations Limited | West Sussex | 2006 |
| Asset Services Group Limited | Ferndown | 2021 |
| Asset Services Limited | Dorset | 1994 |
| Asset Shield Ltd | London | 2026 |
| Asset Snap Ltd | Lancaster | 2025 |
| Asset Streamline Ltd | Grays | 2015 |
| Asset Tagged Limited | Warminster | 2024 |
| Asset Tech Solutions Limited | Clacton-On-Sea | 2025 |
| Asset Technologies (London) Ltd | Barry | 2002 |
| Asset Technology Limited | Stockport | 2015 |
| Asset Ventures Ltd | London | 2024 |
| Asset Vision Limited | Solihull | 2022 |
| Asset Workflows Ltd | London | 2026 |
| Asset.Tv Limited | London | 2015 |
| ASSET27 Limited | Sheffield | 2016 |
| Assetbrain Technology Limited | London | 2025 |
| Assetcore Limited | Northwich | 2015 |
| Assetence Limited | Buckhurst Hill | 2025 |
| Assetgen Limited | Swindon | 1985 |
| Assetind Ltd | London | 2023 |
| Assetlogic International Ltd | Godalming | 2021 |
| Assetmap.Io Limited | Pinner | 2014 |