| 1ST Locate (UK) Limited | Leeds | 1999 |
| 1ST Logic Limited | London | 2017 |
| 1ST Look Ltd | Stratford-Upon-Avon | 1996 |
| 1ST MAY Ltd | Mansfield Woodhouse | 2018 |
| 1ST Media Hosting Ltd | London | 2011 |
| 1ST Place Information Technology Limited | Westcliff-On-Sea | 2008 |
| 1ST Position Vehicles Limited | | 2000 |
| 1ST Projects Limited | Birmingham | 2010 |
| 1ST QA Ltd | Telford | 2019 |
| 1ST Rate Aerials and Satellites Ltd | Seaford | 2012 |
| 1ST Shika Limited | Croydon | 2013 |
| 1ST Soft Limited | London | 2019 |
| 1ST Sparks Ltd | Walton-On-Thames | 2014 |
| 1ST Step Managment Ltd | London | 2022 |
| 1ST Street Ltd | Barking | 2021 |
| 1ST Take Ltd | London | 2005 |
| 1ST Tech Advance Limited | London | 2026 |
| 1ST Tech Group Limited | Malvern | 2022 |
| 1ST Tech Solutions Limited | Nottingham | 2017 |
| 1ST Technologies (Holding) Limited | Preston | 2013 |
| 1ST Technologies Ltd | Preston | 1997 |
| 1ST Technology Services Ltd | Waltham Cross | 2022 |
| 1ST Tecno Solutions Ltd | Preston | 2022 |
| 1ST Unicorns Consultant Limited | Dalkeith | 2025 |
| 1ST View TV Ltd | Stanmore | 2021 |
| 1ST Web Ltd | Bury St. Edmunds | 2026 |
| 1ST Webdesigns Limited | Leicester | 2001 |
| 1ST XV Films Limited | London | 2011 |
| 1ST-COMPUTERS Solutions Ltd | Bolton | 2012 |
| 1ST24 Ltd | London | 2024 |
| 1ST4 Business Solutions Limited | Prenton | 2012 |
| 1STADIA UK Limited | Uxbridge | 2023 |
| 1STAVEMACHINEUK Ltd | London | 2021 |
| 1STDIBS.COM Ltd. | Bedford | 2004 |
| 1STEIGHTEEN Ltd | London | 2025 |
| 1STEP Housing Limited | Ilford | 2023 |
| 1STEP2MARKET Limited | London | 2020 |
| 1STHAND Consultancy Ltd | Kington | 2017 |
| 1STKINGS Ltd | Doncaster | 2026 |
| 1STKLASS Ltd | Welling | 2025 |
| 1STOP ICT Solutions Ltd | London | 2020 |
| 1STOP4THIRDSECTOR Ltd | Isle Of Harris | 2017 |
| 1STRETAILSOLUTIONS Limited | Colchester | 2018 |
| 1STSOLUTIONS Ltd | London | 2021 |
| 1STWELLBEING Ltd | Wolverhampton | 2018 |
| 1SWAP Limited | London | 2025 |
| 1T Consultancy Ltd | Redditch | 2016 |
| 1T Solutions Limited | Rotherham | 2001 |
| 1T Support Ltd | London | 2021 |
| 1T Testing Limited | Bognor Regis | 2016 |
| 1TAP App Limited | London | 2016 |
| 1TECHAI Ltd | Oldbury | 2025 |
| 1TECHNO Limited | Manchester | 2014 |
| 1TH Limited | Lytham St Annes | 2024 |
| 1TIMETABLE Ltd | Leeds | 2024 |
| 1TK Games Development Ltd | Canterbury | 2024 |
| 1TK Games Ltd | Canterbury | 2024 |
| 1TO1 Books Ltd | London | 2025 |
| 1TOUCH Media Ltd | Weybridge | 2021 |
| 1TOUCH Productions Limited | Bracknell | 2019 |
| 1TRUTH Limited | Belfast | 2015 |
| 1TVTR Ltd | Horsham | 2025 |
| 1TWO1 Services and Allied Limited | London | 2026 |
| 1TWO4 Productions Ltd | London | 2024 |
| 1TWOAPPS Limited | London | 2022 |
| 1UP Consulting Ltd | Batley | 2013 |
| 1UP Metaverse Creative Limited | London | 2022 |
| 1UP Mvct Limited | London | 2025 |
| 1UP QA Services Ltd | Glasgow | 2019 |
| 1UT Ltd | Pinner | 2025 |
| 1VENT Media Ltd | Salford | 2025 |
| 1VOICE - Communicating Together | Lymm | 2010 |
| 1WAYBET Ltd | London | 2025 |
| 1WIN Mobile App Studio Ltd | London | 2025 |
| 1WORD Productions Ltd | Salford | 2022 |
| 1WORLDSYNC Ltd. | London | 2019 |
| 1X1 Apps Limited | London | 2015 |
| 1X2 Consulting Ltd | Chepstow | 2023 |
| 1X2 Network Ltd | Brentwood | 2020 |
| 1X2 Network Software Ltd | Brentwood | 2021 |
| 1ZERO Digital Limited | Cheltenham | 2015 |
| 2 Aardvarks Ltd | Wimborne | 2014 |
| 2 Advanced Networks Ltd | Leigh-On-Sea | 2010 |
| 2 and a BIT Ltd | London | 2024 |
| 2 Beards Games Ltd | Liverpool | 2023 |
| 2 Bears Software Limited | London | 2026 |
| 2 Birds and a Camera Ltd | Liverpool | 2020 |
| 2 BIT Networking Ltd | London | 2018 |
| 2 BIT Solutions Limited | London | 2004 |
| 2 Brookes Consulting Limited | Berkshire | 2007 |
| 2 Bubblin Records Limited | London | 2009 |
| 2 Buttons Limited | London | 2016 |
| 2 by 2 Websites Ltd | Huddersfield | 2021 |
| 2 Circles Communications Limited | Dummer | 2022 |
| 2 Connect Media Ltd | London | 2023 |
| 2 Coves Technology Ltd. | St. Austell | 2011 |
| 2 Create Film & Television Limited | Hemel Hempstead | 2004 |
| 2 Data for YOU Ltd | Liverpool | 2024 |
| 2 Degrees West Ltd | Bristol | 2016 |
| 2 Endeavour Limited | London | 2024 |