| 1 | Renaissance Learning UK Limited Swindon Turnover £23.6M | £521.2M 2024 accounts | £23.6M |
| 2 | Sopra Steria Limited London Turnover £436.4M | £497.4M | £436.4M |
| 3 | Constellation Software UK Holdco Ltd Chippenham | £340.3M 2024 accounts | — |
| 4 | Ansys UK Limited Sheffield | £314.0M 2024 accounts | — |
| 5 | Tech Mahindra London Limited London | £307.3M 2023 accounts | — |
| 6 | Trailfinders Limited | £292.0M 2022 accounts | — |
| 7 | Volaris Group UK Holdco Ltd Chorley Turnover £9.3M | £235.6M 2024 accounts | £9.3M |
| 8 | Sopra Steria UK Corporate Limited London | £213.4M | — |
| 9 | Causeway Technologies Holdings Limited Gerrards Cross | £211.6M | — |
| 10 | Mri Software Community & Housing Limited London Turnover £27.6M | £210.7M 2024 accounts | £27.6M |
| 11 | Causeway Technologies Limited Gerrards Cross | £203.2M | — |
| 12 | Softov Limited Dunmow Turnover £13.5M | £200.5M | £13.5M |
| 13 | Openbet Limited London | £173.4M | — |
| 14 | Scopely Explore International Limited Bristol Turnover £701.0M | £133.7M | £701.0M |
| 15 | NCR Limited London | £128.4M 2024 accounts | — |
| 16 | Luxoft UK Limited Farnborough Turnover £25.1M | £121.5M 2021 accounts | £25.1M |
| 17 | Snap-On Business Solutions Limited Reading Turnover £37.8M | £115.6M 2020 accounts | £37.8M |
| 18 | Kinetic Games Limited Southampton | £106.3M | — |
| 19 | Magellan Services UK Limited Nottingham Turnover £81.3M | £99.6M 2023 accounts | £81.3M |
| 20 | Ebblo UK Limited Chippenham Turnover £12.0M | £96.8M 2024 accounts | £12.0M |
| 21 | Openbet Technologies Limited London | £94.3M | — |
| 22 | HFD Datavita Limited Glasgow Turnover £11.9M | £91.9M | £11.9M |
| 23 | Gismart Limited London Turnover £61.3M | £86.9M 2020 accounts | £61.3M |
| 24 | Facepunch Studios Ltd Birmingham Turnover £87.9M | £82.3M | £87.9M |
| 25 | Data Grid Solutions PLC London Turnover £339.2k | £76.9M | £339.2k |
| 26 | Insightsoftware UK Ltd London Turnover £34.4M | £75.1M 2024 accounts | £34.4M |
| 27 | Naturalmotion Games Limited London | £74.1M 2023 accounts | — |
| 28 | Wisetech Global (UK) Ltd. London Turnover £23.0M | £70.8M 2024 accounts | £23.0M |
| 29 | Otto Car Limited London Turnover £51.2M | £63.4M 2024 accounts | £51.2M |
| 30 | Avecto Ltd Manchester | £63.4M | — |
| 31 | Mri Software Emea Limited London Turnover £46.7M | £57.3M 2024 accounts | £46.7M |
| 32 | Monotype Limited London Turnover £59.6M | £50.8M | £59.6M |
| 33 | Panecea Group Limited Guildford | £48.0M | — |
| 34 | Hippo Digital Limited Leeds Turnover £73.2M | £47.1M 2025 accounts | £73.2M |
| 35 | Double Eleven Limited Middlesbrough | £47.0M | — |
| 36 | Enghouse Interactive (UK) Limited Reading Turnover £23.8M | £47.0M 2019 accounts | £23.8M |
| 37 | Enghouse Holdings (UK) Limited Staines-Upon-Thames Turnover £1.6M | £44.7M 2019 accounts | £1.6M |
| 38 | Dataart Technologies UK Ltd London | £43.8M | — |
| 39 | Smart Card Software Limited Swanley Turnover £0 | £42.3M 2023 accounts | £0 |
| 40 | Fletchers Solicitors Limited Manchester Turnover £34.1M | £40.8M 2022 accounts | £34.1M |
| 41 | SS&C Solutions Limited London | £39.3M 2024 accounts | — |
| 42 | Epic Bristol Limited Salford Turnover £138.3M | £38.8M | £138.3M |
| 43 | Tsys Card Tech Limited London Turnover £71.7M | £38.6M | £71.7M |
| 44 | Selina Finance Limited London | £37.0M 2021 accounts | — |
| 45 | Cloudflare Limited London Turnover £80.7M | £32.9M 2021 accounts | £80.7M |
| 46 | Intellect Design Arena Limited London | £31.6M 2025 accounts | — |
| 47 | Ripple Markets UK Ltd London | £30.0M 2023 accounts | — |
| 48 | SGX FX Systems UK Limited London Turnover £29.4M | £29.5M 2021 accounts | £29.4M |
| 49 | MHR International UK Limited Ruddington Turnover £134.5M | £28.7M 2024 accounts | £134.5M |
| 50 | Management Refined Limited London | £28.6M | — |
| 51 | Magmatic Games Ltd Kingston Upon Thames Turnover £71.5M | £27.5M 2024 accounts | £71.5M |
| 52 | Bright SG Limited Leamington Spa Turnover £16.3M | £26.9M | £16.3M |
| 53 | Next Ventures Limited London Turnover £89.7M | £26.3M 2024 accounts | £89.7M |
| 54 | Koei Tecmo Europe Limited Letchworth Garden City | £26.3M 2025 accounts | — |
| 55 | Argus Software (UK) Ltd. London Turnover £12.5M | £26.0M 2024 accounts | £12.5M |
| 56 | Modaxo Group UK Limited Chippenham Turnover £11.1M | £24.2M | £11.1M |
| 57 | Ghost Town Games Ltd. London | £23.5M 2024 accounts | — |
| 58 | XBP Europe Limited Egham Turnover £25.7M | £23.4M 2024 accounts | £25.7M |
| 59 | Toyota Connected Europe Limited London Turnover £41.2M | £22.2M 2024 accounts | £41.2M |
| 60 | Godel Technologies Europe Limited Manchester Turnover £81.2M | £21.9M 2023 accounts | £81.2M |
| 61 | Tma Data Management Limited Kingston Upon Thames | £20.8M | — |
| 62 | Auth0 Ltd. London | £20.5M 2025 accounts | — |
| 63 | Truelayer Limited London | £19.8M 2024 accounts | — |
| 64 | Rategain Technologies Limited London | £19.4M 2021 accounts | — |
| 65 | Metropress Limited London Turnover £15.9M | £19.3M 2019 accounts | £15.9M |
| 66 | Edesix Limited Edinburgh | £19.1M 2024 accounts | — |
| 67 | Ruth Miskin Literacy Limited London Turnover £13.3M | £19.0M | £13.3M |
| 68 | Barron McCann Limited Derby Turnover £25.3M | £18.9M | £25.3M |
| 69 | Faculty Science Limited London Turnover £41.7M | £18.0M | £41.7M |
| 70 | Mongodb UK Limited London Turnover £81.0M | £17.9M 2025 accounts | £81.0M |
| 71 | Comcarde Limited Edinburgh | £17.9M 2023 accounts | — |
| 72 | Circle It Solutions Limited Liverpool Turnover £24.9M | £17.8M 2024 accounts | £24.9M |
| 73 | Egain Communications Ltd Newbury Turnover £15.2M | £17.6M | £15.2M |
| 74 | Assistive Solutions Ltd London Turnover £39.4M | £17.5M | £39.4M |
| 75 | Logiq Consulting Ltd Bristol | £17.3M | — |
| 76 | Sword It Solutions Limited Staines-Upon-Thames Turnover £50.0M | £17.2M 2024 accounts | £50.0M |
| 77 | Viking Digital Ecit Limited Leicester Turnover £10.1M | £17.1M 2021 accounts | £10.1M |
| 78 | MDS Cem Holdings Limited Warrington | £16.9M 2024 accounts | — |
| 79 | Boston Limited St. Albans Turnover £72.3M | £16.5M 2023 accounts | £72.3M |
| 80 | Columbus Global UK Ltd Nottingham Turnover £41.7M | £16.5M 2024 accounts | £41.7M |
| 81 | Napo Limited London | £16.4M 2024 accounts | — |
| 82 | Absolutely No Nonsense Admin Ltd Cardiff | £16.4M 2019 accounts | — |
| 83 | Deepl UK Ltd. London Turnover £43.9M | £16.3M | £43.9M |
| 84 | Lablogic Group Holdings Limited Sheffield | £16.2M | — |
| 85 | Lindar Media Limited St. Albans | £16.0M 2024 accounts | — |
| 86 | Supermassive Games 1 Limited Eastleigh | £15.8M 2022 accounts | — |
| 87 | Luxon Payments Ltd Nottingham | £15.6M 2024 accounts | — |
| 88 | Clover Bidco Limited Nottingham | £15.3M 2023 accounts | — |
| 89 | Microlink PC (UK) Limited Chandlers Ford Turnover £9.4M | £15.0M | £9.4M |
| 90 | Dolby Europe Limited London Turnover £20.1M | £15.0M | £20.1M |
| 91 | Redis Emea Ltd. London | £14.9M | — |
| 92 | Odyssey Interactive Limited Manchester | £14.9M 2024 accounts | — |
| 93 | Workfront, Ltd. Reading Turnover £16.7M | £14.7M 2024 accounts | £16.7M |
| 94 | Luxoft Financial Services UK Limited Farnborough Turnover £58.0M | £14.7M 2021 accounts | £58.0M |
| 95 | Otas Technologies Holding Ltd London | £14.7M 2020 accounts | — |
| 96 | Quantcast Limited London Turnover £18.6M | £14.4M 2023 accounts | £18.6M |
| 97 | Deltek GB Limited London | £14.1M 2024 accounts | — |
| 98 | Elsewhen Ltd London | £13.9M 2024 accounts | — |
| 99 | Techbuyer Limited Harrogate Turnover £52.1M | £13.9M | £52.1M |
| 100 | Medical Information Technology UK Ltd London Turnover £33.1M | £13.7M | £33.1M |
| 101 | Calrom Management Limited Ellesmere Port | £13.7M | — |
| 102 | Redbrain Limited Tamworth | £13.7M 2024 accounts | — |
| 103 | Perk UK Ltd Birmingham Turnover £33.3M | £13.4M 2021 accounts | £33.3M |
| 104 | Chainalysis UK Limited London Turnover £21.9M | £13.0M | £21.9M |
| 105 | Torry Harris Business Solutions (Europe) Ltd Bristol Turnover £29.9M | £13.0M 2025 accounts | £29.9M |
| 106 | Dataline Software Limited Reading | £12.9M 2019 accounts | — |
| 107 | Macs EU Limited Birmingham | £12.6M | — |
| 108 | Inverto UK Limited London | £12.2M 2024 accounts | — |
| 109 | Zwift UK Ltd Bristol Turnover £13.6M | £12.2M 2025 accounts | £13.6M |
| 110 | Mri Software Solutions Limited London Turnover £18.0M | £12.1M 2024 accounts | £18.0M |
| 111 | Soracom Corporation, Ltd. London | £11.7M | — |
| 112 | Cex.Io Ltd London Turnover £10.0M | £11.7M | £10.0M |
| 113 | Apron Payments Ltd London | £11.5M 2023 accounts | — |
| 114 | Perseus Group Software Ltd Poole Turnover £300.3k | £11.5M | £300.3k |
| 115 | Affiliate Squared Ltd Brentwood | £11.4M | — |
| 116 | Bloomreach UK Ltd London Turnover £24.7M | £11.3M | £24.7M |
| 117 | Unrvld Ltd London Turnover £18.5M | £11.3M 2025 accounts | £18.5M |
| 118 | Adaptive Financial Consulting Limited London | £11.2M 2021 accounts | — |
| 119 | Htec Limited London Turnover £10.4M | £11.2M 2024 accounts | £10.4M |
| 120 | Safenames Ltd Milton Keynes Turnover £20.8M | £11.2M | £20.8M |
| 121 | The Justice Platform Ltd London | £11.2M 2023 accounts | — |
| 122 | Aire Logic Limited Leeds Turnover £42.2M | £10.9M 2024 accounts | £42.2M |
| 123 | Bound Rates Limited London | £10.9M 2022 accounts | — |
| 124 | Forescout Technologies UK Ltd London Turnover £16.3M | £10.9M | £16.3M |
| 125 | Plan.Nr Limited London Turnover £10.5M | £10.8M 2025 accounts | £10.5M |
| 126 | Atex Media Limited Bristol Turnover £2.7M | £10.8M 2024 accounts | £2.7M |
| 127 | Avco Systems Limited Slough | £10.6M | — |
| 128 | Box Technologies Limited Thame Turnover £15.7M | £10.6M 2024 accounts | £15.7M |
| 129 | Wellington Computer Systems Limited Belfast Turnover £10.3M | £10.4M 2024 accounts | £10.3M |
| 130 | Networks Centre Limited Ashington Turnover £41.6M | £10.4M | £41.6M |
| 131 | Magnitude Software UK Limited London Turnover £1.4M | £10.4M 2024 accounts | £1.4M |
| 132 | Consult Red Limited Shipley Turnover £27.3M | £10.4M 2023 accounts | £27.3M |
| 133 | Seebyte Limited Edinburgh Turnover £10.8M | £10.4M 2024 accounts | £10.8M |
| 134 | UK Web Media Limited Southampton Turnover £13.6M | £10.3M | £13.6M |
| 135 | Sprinklr UK Ltd London Turnover £29.7M | £10.3M 2025 accounts | £29.7M |
| 136 | Mayden House Limited Bath Turnover £12.6M | £10.3M | £12.6M |
| 137 | Hybrid Services Limited Crewe | £10.3M | — |
| 138 | Matterport (UK) Sales Ltd London Turnover £10.0M | £10.2M 2024 accounts | £10.0M |
| 139 | Hexaware Technologies UK Limited London Turnover £101.3M | £10.2M 2021 accounts | £101.3M |
| 140 | Cprime Limited Leeds Turnover £15.0M | £10.2M 2024 accounts | £15.0M |
| 141 | Giving.Com Limited London Turnover £64.5M | £10.2M | £64.5M |
| 142 | Kaizen Reporting Limited London Turnover £15.3M | £10.1M 2024 accounts | £15.3M |
| 143 | Rex Brown Limited London | £10.1M 2024 accounts | — |
| 144 | Contechs Consulting Limited Basildon Turnover £49.7M | £10.0M 2023 accounts | £49.7M |
| 145 | Euro Options Limited Littleborough | £10.0M | — |
| 146 | Fusion Business Solutions (UK) Limited Sunbury-On-Thames Turnover £18.2M | £9.9M 2022 accounts | £18.2M |
| 147 | Edtc Ltd London Turnover £10.1M | £9.9M 2024 accounts | £10.1M |
| 148 | Jaja Finance Ltd London Turnover £12.8M | £9.9M 2021 accounts | £12.8M |
| 149 | Pinterest UK Ltd London Turnover £44.1M | £9.9M 2024 accounts | £44.1M |
| 150 | Whitehall Resources Limited Colchester | £9.9M | — |
| 151 | Imperial Civil Enforcement Solutions Limited Northampton Turnover £15.5M | £9.8M | £15.5M |
| 152 | Sapiens (UK) Limited London | £9.8M 2022 accounts | — |
| 153 | Send Technology Solutions Limited London | £9.8M 2024 accounts | — |
| 154 | Foods Connected Ltd Londonderry | £9.7M 2024 accounts | — |
| 155 | Codethink Limited Manchester | £9.7M 2024 accounts | — |
| 156 | Mba Michael Bailey Associates PLC London | £9.6M 2024 accounts | — |
| 157 | Juxt Ltd. London | £9.5M | — |
| 158 | MDS Global Ltd Warrington Turnover £19.6M | £9.5M 2024 accounts | £19.6M |
| 159 | Sight and Sound Technology Limited Northampton Turnover £34.0M | £9.4M | £34.0M |
| 160 | I.T. Professional Services Limited Chester Le Street | £9.4M | — |
| 161 | Codeweavers Limited Stafford | £9.3M 2024 accounts | — |
| 162 | Skiddle Limited Preston Turnover £18.2M | £9.3M 2025 accounts | £18.2M |
| 163 | Alterian Technology Limited Maidenhead | £9.3M 2021 accounts | — |
| 164 | Astound Commerce Ltd. London Turnover £13.0M | £9.1M | £13.0M |
| 165 | IC Consult UK Limited London Turnover £17.5M | £8.9M 2024 accounts | £17.5M |
| 166 | Visavvi Limited Birmingham | £8.9M 2025 accounts | — |
| 167 | Datascope Systems Limited Chester | £8.9M | — |
| 168 | Medius Software Limited Manchester Turnover £13.0M | £8.8M 2022 accounts | £13.0M |
| 169 | DGL Healthcare Technology Limited London Turnover £4.8M | £8.8M 2024 accounts | £4.8M |
| 170 | Maverick Games Limited London | £8.7M 2024 accounts | — |
| 171 | Intragen Holdings Limited London | £8.6M 2024 accounts | — |
| 172 | Misco Technologies Limited Rushden Turnover £119.3M | £8.5M | £119.3M |
| 173 | Ikonic Technology Limited Heywood | £8.5M | — |
| 174 | Saepio Solutions Limited High Wycombe | £8.3M | — |
| 175 | Attapoll Ltd London | £8.3M | — |
| 176 | Synergy Health Systems Limited Basingstoke | £8.3M | — |
| 177 | Quantanite UK Limited London | £8.2M 2024 accounts | — |
| 178 | Rimini Street Limited London Turnover £18.2M | £8.2M 2024 accounts | £18.2M |
| 179 | Access Computer Consulting PLC London | £8.2M | — |
| 180 | Myworkpapers Group Limited Leamington Spa | £8.1M | — |
| 181 | Innov8 Technology Ltd Heaton Mersey Stockport | £8.1M | — |
| 182 | Robiquity Limited Manchester Turnover £16.4M | £8.1M | £16.4M |
| 183 | Guidewire Software (UK) Limited London | £8.0M 2023 accounts | — |
| 184 | Socially Powerful Media Limited London Turnover £24.3M | £8.0M | £24.3M |
| 185 | Digitalocean Droplet Limited London Turnover £12.4M | £8.0M | £12.4M |
| 186 | RDX Works Ltd London | £8.0M 2021 accounts | — |
| 187 | Mandata (Management and Data Services) Ltd Newcastle Upon Tyne Turnover £11.1M | £8.0M 2024 accounts | £11.1M |
| 188 | Apadmi Limited Salford Turnover £26.4M | £8.0M | £26.4M |
| 189 | TVG Media Limited Bristol Turnover £10.3M | £8.0M 2025 accounts | £10.3M |
| 190 | Abtec Network Systems Ltd. Market Harborough | £8.0M 2024 accounts | — |
| 191 | Eurobase Systems Limited Chelmsford | £7.9M | — |
| 192 | Snowplow Analytics Limited London | £7.9M 2021 accounts | — |
| 193 | Remarkable Internet Ltd Nottingham Turnover £9.0M | £7.8M | £9.0M |
| 194 | Ecarx Limited London Turnover £0 | £7.8M 2022 accounts | £0 |
| 195 | Payment Card Solutions (UK) Limited London | £7.8M | — |
| 196 | Cheshire Datasystems Limited Stockport Turnover £29.6M | £7.7M | £29.6M |
| 197 | Antser Group Limited Birmingham | £7.7M | — |
| 198 | Thoughtspot Emea Limited London Turnover £16.0M | £7.7M | £16.0M |
| 199 | Centurion Management Systems Limited Horsham Turnover £12.9M | £7.6M 2024 accounts | £12.9M |
| 200 | Vipr Limited London Turnover £12.1M | £7.6M | £12.1M |
| 201 | Content Square Ltd London Turnover £33.7M | £7.6M | £33.7M |
| 202 | Right Group Holdings Limited London | £7.6M 2022 accounts | — |
| 203 | Socialrel8 Ltd Middlesbrough | £7.5M 2024 accounts | — |
| 204 | Cameo Computer Services (UK) Limited Broughton Astley Turnover £15.8M | £7.5M | £15.8M |
| 205 | Insignis Asset Management Limited Cambridge Turnover £20.5M | £7.4M | £20.5M |
| 206 | Castleton Technologies Limited London Turnover £13.4M | £7.3M 2024 accounts | £13.4M |
| 207 | Nuance Communications UK Limited London Turnover £18.1M | £7.3M 2021 accounts | £18.1M |
| 208 | Acuma Solutions Limited Harrow Turnover £17.0M | £7.3M 2025 accounts | £17.0M |
| 209 | Praesto Consulting UK Ltd Darlington Turnover £13.1M | £7.2M 2024 accounts | £13.1M |
| 210 | Mutual Vision Technologies Limited Wilmslow | £7.2M | — |
| 211 | Graitec Limited Southampton | £7.1M | — |
| 212 | Amadeus Hospitality UK Limited Hounslow Turnover £10.6M | £7.1M 2020 accounts | £10.6M |
| 213 | User Testing Limited Edinburgh Turnover £13.1M | £6.9M | £13.1M |
| 214 | Backbase UK Limited London | £6.9M 2024 accounts | — |
| 215 | Systal Technology Solutions Limited Glasgow Turnover £43.9M | £6.8M 2024 accounts | £43.9M |
| 216 | Cloudrock Partners Ltd London | £6.8M 2023 accounts | — |
| 217 | Sponge Group Limited Bristol | £6.8M 2022 accounts | — |
| 218 | A 2 C Services Limited Portsmouth Turnover £21.9M | £6.8M 2023 accounts | £21.9M |
| 219 | 15below Limited Brighton | £6.7M 2023 accounts | — |
| 220 | Accurx Limited London | £6.7M 2020 accounts | — |
| 221 | The Config Team Limited Milnthorpe | £6.7M | — |
| 222 | Monday.Com UK 2020 Ltd. London Turnover £22.9M | £6.7M 2023 accounts | £22.9M |
| 223 | TS Imagine (UK) Ltd London | £6.7M 2024 accounts | — |
| 224 | Data Intellect Services Limited Belfast | £6.7M 2020 accounts | — |
| 225 | E Fundamentals (International) Limited London | £6.7M | — |
| 226 | Acrotrend Solutions Limited Hemel Hempstead Turnover £4.5M | £6.6M | £4.5M |
| 227 | CDS Support Limited Cheltenham Turnover £19.4M | £6.6M 2024 accounts | £19.4M |
| 228 | Opencast Software Europe Limited Newcastle Upon Tyne Turnover £49.9M | £6.6M 2023 accounts | £49.9M |
| 229 | Acorah Software Products Limited Wokingham Turnover £13.0M | £6.6M 2024 accounts | £13.0M |
| 230 | Switchshop Limited Hitchin | £6.5M | — |
| 231 | Nimble Delivery Limited Sheffield | £6.4M | — |
| 232 | Informed Solutions Limited Cheshire | £6.4M | — |
| 233 | Firesprite Limited London | £6.3M 2020 accounts | — |
| 234 | Fleet Claims Administration Limited Bicester | £6.3M 2025 accounts | — |
| 235 | Hiperdist Limited Camberley Turnover £102.0M | £6.3M 2024 accounts | £102.0M |
| 236 | Turn It on Limited Witney Turnover £18.1M | £6.3M 2025 accounts | £18.1M |
| 237 | Resulting Limited Warrington | £6.3M 2024 accounts | — |
| 238 | Pdf-Xchange Co Ltd Reigate Turnover £15.9M | £6.3M | £15.9M |
| 239 | Cisilion Limited Leatherhead | £6.3M | — |
| 240 | A.S.K. Partners Limited London | £6.2M 2023 accounts | — |
| 241 | Greenzone Software Development Limited Newark | £6.2M 2024 accounts | — |
| 242 | Sweatco Ltd London Turnover £15.0M | £6.1M 2024 accounts | £15.0M |
| 243 | Harbor Solutions Limited Beaconsfield | £6.1M | — |
| 244 | Comarch UK Ltd London | £6.1M 2019 accounts | — |
| 245 | Intralinks Ltd. London Turnover £18.9M | £6.0M 2024 accounts | £18.9M |
| 246 | Entertainment Partners UK Limited Wokingham | £6.0M | — |
| 247 | Leading Resolutions Limited Swindon | £6.0M 2024 accounts | — |
| 248 | Caresoft Global Limited Basildon | £5.9M | — |
| 249 | Sterling Management Centre Limited Barrow In Furness | £5.8M 2024 accounts | — |
| 250 | Gen2 Systems Limited Birmingham Turnover £12.1M | £5.8M 2024 accounts | £12.1M |
| 251 | Madgex Limited Bognor Regis Turnover £6.8M | £5.8M 2021 accounts | £6.8M |
| 252 | Barracuda Networks Limited Reading Turnover £28.3M | £5.8M | £28.3M |
| 253 | The Information Lab Limited London Turnover £39.6M | £5.7M 2025 accounts | £39.6M |
| 254 | C&C Group Holdings Limited Redhill | £5.7M | — |
| 255 | Imaginera Limited Warwick | £5.7M 2022 accounts | — |
| 256 | Automation Anywhere UK Limited London | £5.6M 2023 accounts | — |
| 257 | LA Micro Group (UK) Limited Bracknell | £5.6M | — |
| 258 | Beyondplay Limited Birmingham | £5.6M 2023 accounts | — |
| 259 | SPS Sportsoft Limited Liverpool | £5.6M | — |
| 260 | Opengamma Limited London | £5.6M | — |
| 261 | Mastek Systems Company Ltd Harrow Turnover £18.9M | £5.6M 2020 accounts | £18.9M |
| 262 | Crosstide Ltd London | £5.6M 2020 accounts | — |
| 263 | Codestone Solutions Limited Poole | £5.5M | — |
| 264 | Quinnox Limited London Turnover £10.5M | £5.5M | £10.5M |
| 265 | Elder Technologies Limited London Turnover £7.0M | £5.5M 2021 accounts | £7.0M |
| 266 | Internet Communications (Services) Limited Bournemouth | £5.5M 2024 accounts | — |
| 267 | Rubber Road Ltd Welwyn Garden City | £5.5M | — |
| 268 | Futurlab Limited Brighton | £5.5M 2023 accounts | — |
| 269 | Ibsecad Limited London Turnover £7.9M | £5.4M | £7.9M |
| 270 | Nomensa Ltd Bournemouth | £5.4M | — |
| 271 | Dufrain Consulting Ltd Edinburgh | £5.4M 2021 accounts | — |
| 272 | E.D.W. Technology Limited Milton Keynes | £5.4M | — |
| 273 | Supersonic Software Limited | £5.4M 2020 accounts | — |
| 274 | Eton Travel Agency Limited Maidenhead | £5.4M | — |
| 275 | Tealium Limited Bicester | £5.3M | — |
| 276 | Forrit Technology Limited London | £5.3M | — |
| 277 | Cleardata UK Limited London | £5.3M | — |
| 278 | Vivos Technology Limited Nether Alderley | £5.3M 2020 accounts | — |
| 279 | Worldline Merchant Services UK Limited London Turnover £16.0M | £5.3M | £16.0M |
| 280 | Transferroom Ltd London | £5.2M 2023 accounts | — |
| 281 | Espire Infolabs Limited London Turnover £29.5M | £5.2M | £29.5M |
| 282 | Managed Information Technologies Limited Waltham Cross Turnover £10.9M | £5.2M 2024 accounts | £10.9M |
| 283 | Liquidnet Technologies Europe Limited London | £5.1M 2020 accounts | — |
| 284 | Excotek Ltd Blackburn | £5.1M 2025 accounts | — |
| 285 | Envitia Ltd Horsham Turnover £10.7M | £5.1M 2024 accounts | £10.7M |
| 286 | Legerity Limited London Turnover £2.8M | £5.1M 2024 accounts | £2.8M |
| 287 | Crown Jewels Consultants Ltd London Turnover £17.2M | £5.1M 2024 accounts | £17.2M |
| 288 | Critical Software Ltd Southampton | £5.1M 2024 accounts | — |
| 289 | Lucid Games Limited Liverpool | £5.1M 2024 accounts | — |
| 290 | BCS Data Centres Limited London | £5.1M | — |
| 291 | Motor Design Limited Reading | £5.0M | — |
| 292 | Pottermore Limited 3 Dorset Rise | £4.9M | — |
| 293 | Symology Limited Dunstable | £4.9M 2025 accounts | — |
| 294 | Merchant Warehouse (NI) Ltd Belfast Turnover £9.3M | £4.9M 2023 accounts | £9.3M |
| 295 | Supermassive Games 3 Limited Eastleigh | £4.9M 2022 accounts | — |
| 296 | Ministry of Automattic Limited London | £4.9M | — |
| 297 | Prophet Limited Copse Drive Meriden | £4.8M | — |
| 298 | Ocf Limited Chapeltown, Sheffield | £4.8M | — |
| 299 | 15Gifts Ltd Crawley Turnover £7.1M | £4.8M | £7.1M |
| 300 | Bright Network (UK) Limited London Turnover £11.6M | £4.8M 2023 accounts | £11.6M |