| 2050 Data Solutions Limited | London | 2026 |
| 2050 AI Limited | London | 2025 |
| 2050 Global Ltd | Bath | 2026 |
| 2050CARDS Ltd | London | 2021 |
| 2050MAX Limited | London | 2026 |
| 2050TERRA Ltd | Edinburgh | 2024 |
| 207 Capital Holdings Limited | Bristol | 2025 |
| 2075 Limited | Milton Keynes | 2025 |
| 2077DIGITAL Ltd | Wembley | 2020 |
| 208 Productions Ltd | Biggleswade | 2011 |
| 2083 Ltd | London | 2024 |
| 209 Consultancy Limited | Manchester | 2015 |
| 2099 Group Ltd | London | 2025 |
| 20:20 SPM Limited | Wantage | 2007 |
| 20D Ltd | London | 2024 |
| 20GOTO10 Ltd | London | 2015 |
| 20I Limited | Mansfield | 2015 |
| 20MINDS Ltd | Cambridge | 2025 |
| 20NINE30ONE Ltd | Bury St Edmunds | 2024 |
| 20Q Limited | Taunton | 2011 |
| 20REV Ltd | Choppington | 2026 |
| 20TECH Ltd | London | 2022 |
| 20TEN Entertainment Ltd | Liverpool | 2010 |
| 20TH Century COX Ltd | London | 2020 |
| 20TH Century Studios UK Global Productions Limited | London | 2013 |
| 20TH Century Studios UK Limited | London | 2008 |
| 20TWENTY Talent Limited | Walsall | 2020 |
| 21 12 Labs Ltd | London | 2023 |
| 21 Aces Ltd | St. Albans | 2026 |
| 21 Applications Ltd | London | 2023 |
| 21 at 12 Ltd | Chepstow | 2022 |
| 21 Capital Ltd | Altrincham | 2023 |
| 21 Cuts Ltd | Wembley | 2023 |
| 21 Degrees Digital Services Limited | Leeds | 2023 |
| 21 Degrees Productions Limited | Leeds | 2024 |
| 21 Degrees Weddings Ltd | Leeds | 2019 |
| 21 Filmworks Ltd | London | 2020 |
| 21 Holdings Limited | London | 2017 |
| 21 Marylebone Limited | London | 2020 |
| 21 Media Group Ltd | Glasgow | 2008 |
| 21 SIX Limited | Curdridge | 2013 |
| 21 SIX Media Limited | Curdridge | 2018 |
| 21 Somerset Ltd | Wellington | 2022 |
| 21 Studios Limited | Rotherham | 2022 |
| 21 TV Ltd | London | 2010 |
| 210 Broadcasting CIC | Reading | 2025 |
| 2109 Solutions Ltd | Rickmansworth | 2023 |
| 2112 Analytics Limited | London | 2026 |
| 2112 IT Limited | Wiltshire | 2007 |
| 212 Business Consulting Ltd | Birmingham | 2013 |
| 212 Digital Enterprises Limited | Denton | 2015 |
| 212 Republic Limited | Manchester | 2013 |
| 212ME Ltd | Edinburgh | 2025 |
| 2141 Limited | London | 2025 |
| 2146 Ltd | Mildenhall | 2019 |
| 217 Limited | Warwick | 2014 |
| 218 Ltd | London | 2018 |
| 219 Art Space Limited | London | 2024 |
| 21:RS Ltd | London | 2021 |
| 21ATOMS Ltd | London | 2024 |
| 21BITCOIN Ltd | London | 2025 |
| 21C Ltd | London | 2021 |
| 21C-TECH Limited | Westcliff-On-Sea | 2022 |
| 21CF Shine Holdings UK Limited | London | 2014 |
| 21CO Technologies Ltd | Altrincham | 2024 |
| 21DIGITAL Limited | Blackburn | 2003 |
| 21ICT Ltd | Swadlincote | 2014 |
| 21J Consulting Ltd | Wembley | 2026 |
| 21RECORDS Limited | Worthing | 2023 |
| 21SCOT Ltd | Glasgow | 2025 |
| 21SIX Publishing Limited | Curdridge | 2009 |
| 21SOUNDS Limited | Worthing | 2023 |
| 21ST 100 Network Ltd. | Hull | 2025 |
| 21ST Century Business Phones Limited | | 1993 |
| 21ST Century Core Technologies Limited | London | 2014 |
| 21ST Century Design Management Ltd | London | 2016 |
| 21ST Century Digital Teaching Limited | London | 2021 |
| 21ST Century Filmworks Limited | Purley | 2009 |
| 21ST Century FOX Limited | Pevensey | 2017 |
| 21ST Century LAN Limited | West Sussex | 2003 |
| 21ST Century Network Solutions Ltd | Southport | 2006 |
| 21ST Century Northern FOX Ltd | Derby | 2015 |
| 21ST Century Productions Limited | Newcastle Upon Tyne | 2019 |
| 21ST Century Publishing Ltd | London | 2021 |
| 21ST Century Solutions Ltd | London | 2009 |
| 21ST Century Television Limited | Kingston Upon Thames | 2002 |
| 21ST Century Web Limited | Hertfordshire | 1997 |
| 21ST Digital Ltd | Ulverston | 1986 |
| 21ST November Ltd | London | 2025 |
| 21ST Webb Ltd | Denbigh | 2015 |
| 21UPMOVEMENT CIC | Chelmsford | 2022 |
| 21V Ltd | London | 2024 |
| 21VH Limited | London | 2026 |
| 21X9 Ltd. | Norwich | 2016 |
| 22 Adventures Limited | London | 2015 |
| 22 Cardamon Project Limited | London | 2025 |
| 22 Cherry Limited | Guildford | 2014 |
| 22 Computing Limited | Kettering | 2015 |
| 22 Consulting Ltd | Montrose | 2014 |
| 22 Degree Media Ltd | Nottingham | 2021 |