Rank Company Location Year end Annual sales rise over 3 years Latest sales £000s Staff Comment
1 LMAX Exchangee-FX trading technology West London Dec 13 307.80% †18,379 98 Its trading technology can process up to 400m orders a day
2 Switch ConceptsAdvertising software developer Southampton Apr 14 262.92% *30,669 120 Its software can place more than 1bn ads online a day
3 SwiftKeySmartphone keyboard developer Central London Dec 13 219.04% 9,884 119 Its technology learns how we type to speed up text prediction on smartphones and tablets
4 Cloud DistributionSecurity and networking provider Berkshire Dec 13 181.00% 9,632 16 Delivers wireless security services for cloud computing
5 Tech21Device impact protection maker Southwest London May 14 171.73% *22,500 44 Uses specialised materials, including a polymer used in bullet-proof glass
6 MobileWebAdzMobile advertising provider Central London Mar 14 142.01% *31,009 81 Its software helps ads appear on 25.5bn mobile internet pages every month
7 CloudSenseCloud computer software provider Central London Jan 14 138.97% *†7,717 121 Has customers in 26 countries
8 Fidelity GroupTelecoms services provider Oxfordshire Dec 13 134.15% *5,670 12 Founders sold two telecoms companies before starting Fidelity
9 Hide My Ass!Online security provider Central London Mar 14 132.48% *10,718 78 Encrypts the online activity of more than 215,000 subscribers
10 Cobalt Light SystemsOptical instrument manufacturer Oxfordshire Jun 14 124.99% *11,641 37 Its technology will help security as restrictions on liquids in aircraft hand luggage end
11 MedicAnimalOnline pet products retailer Northwest London Dec 13 122.02% *71,361 231 Says it is Europe’s largest online retailer of veterinary products
12 OmnifoneDigital music provider Central London Apr 13 121.72% 46,870 181 Its MusicStation platform is available in 35 countries offering 35m tracks
13 Deeper BlueDigital media & events firm Central London Aug 13 118.11% 5,188 8 Earlier this year it opened an office in Bangalore as it targets growth into Asia
14 UnrulyVideo advertising platform Central London Mar 13 117.47% 19,313 123 Claims to have tracked 430bn video views since 2006
15 ECSIT services provider Glasgow Dec 13 116.68% *38,925 134 Customers span the oil and gas, banking, retail and manufacturing sectors
16 Prepaid Financial ServicesPayment services provider Central London Dec 13 115.68% 10,401 41 Is licensed to issue e-money in 43 countries and territories
17 SkimlinksMarketing technology developer Central London Jun 13 113.91% 13,346 53 Helps websites generate revenue from their content
18 EVWellbore diagnosis technology Norwich Mar 14 109.00% *19,570 101 Designs cameras that can be used up to 10km underground
19 SomoMobile marketing services provider Central London Dec 13 108.22% *23,067 130 Customers include Audi, De Beers, BP, Home Depot and Tesco
20 Invenio Business SolutionsIT consultancy Reading Mar 14 106.54% *10,938 403 Has offices in America, Germany, Dubai and seven in India
21 The Exchange LabDigital advertising provider Central London Dec 13 99.02% *15,328 81 Claims to be the world’s largest programmatic marketplace
22 Infinity SDCDatacentre services provider Central London Mar 14 98.26% *21,670 65 Is locating its largest data centre in London’s Olympic Park
23 SkyscannerTravel search engine Edinburgh Dec 13 95.52% 65,819 377 Its app has been downloaded more than 30m times
24 musicMagpie.co.ukOnline entertainment trader Cheshire May 13 95.15% 84,160 1,074 Recently launched an American website, Decluttr.com
25 PotatoDigital marketing agency Central London Mar 14 95.04% *5,755 65 Works on complex web applications for Google and Skype
26 AlertMeSmart home monitoring provider Central London Dec 13 94.99% *18,653 77 Has moved its headquarters from Silicon Fen to Silicon Roundabout
27 Equal ExpertsSoftware developer Central London Mar 14 90.16% *23,792 225 Is using its private sector experience to help the UK government roll out its digital strategy
28 MVFDigital marketing services North London Mar 14 89.97% *18,147 156 Its marketing platform helps clients reach new customers in more than 50 countries
29 The App BusinessMobile app developer Central London Apr 14 88.59% *5,112 53 The first app it built was for Gordon Brown when he was prime minister
30 ZutoCar finance specialist Cheshire Feb 14 87.97% *11,453 220 Its technology facilitates more than £22m of loans each month
31 Mansion House ConsultingIT consultancy Central London Jan 14 85.26% *19,407 41 Has attracted top banks as clients even though it was launched during the financial crisis
32 ChargemasterElectric car charging equipment developer Luton Dec 13 83.87% 5,455 41 Says it is the largest supplier of electric vehicle charging equipment in the UK
33 BrandwatchSocial media monitoring technology Brighton Dec 13 81.86% 8,804 127 Collects 200m pieces of online data every day
34 R-Com ConsultingIT consultancy Greater Manchester Dec 13 81.57% *7,095 23 Diverse client list includes Trust Ford and Manchester Metropolitan University
35 PulsantIT services provider Reading Dec 13 79.13% 43,729 172 Is hosting Scotland’s first dedicated internet exchange point in Edinburgh
36 eTech SolutionsSurveying software developer Solihul Mar 14 76.93% *5,919 107 More than 6,000 separate users employ its mobile surveying software
37 Virtual1Network services provider Central London Mar 14 76.22% *9,212 51 Says it has the largest fibre network in London
38 NtegraIT consultancy Newbury May 14 73.92% *14,595 81 Runs tours of Silicon Valley for chief information officers and IT directors
39 Evolve TelecomTelecoms services provider Essex Sep 13 73.78% 20,261 106 Says it is the second largest Vodafone platinum partner in the UK
40 SilixaSensor technology developer Hertfordshire Dec 13 73.65% 5,119 60 The founders started the business in a garage with equipment bought on eBay
41 ApicalImaging technology developer Central London Mar 14 73.39% *12,772 60 Qualcomm's mobile phone processors use its technology
42 CalastoneFund transaction network Central London Sep 13 72.31% 7,793 75 Says it has enabled the industry to reduce its transaction costs by 60%
43 Simplify DigitalProduct comparison software developer West London Jan 14 70.97% *15,882 76 Helps people compare 1.5m digital TV, phone and broadband packages
44 BCSGIT consultancy Central London Jul 13 69.59% 13,676 86 Has helped more than 200,000 small businesses choose the right software
45 CRFSNetwork monitoring tools developer Cambridge Mar 14 69.27% *5,617 30 Supplied systems for the 2014 World Cup in Brazil
46 E-LeatherEco-friendly materials developer Peterborough Apr 13 68.72% 8,362 98 Has developed a way to make leather lighter and more durable
47 EdenhouseIT consultancy Warwickshire Mar 14 68.16% 15,562 121 Became a Microsoft Dynamics partner in July
48 MaxymiserOnline customer experience optimisation Central London Dec 13 66.01% *15,061 252 Works with some of the world’s biggest brands, including IBM and Hiscox
49 Olive Business SolutionsTelecoms services provider High Wycombe Jan 14 65.75% *19,648 160 Has worked with more than 7,000 UK firms to improve their communication systems
50 Reward GatewayEmployee engagement technology provider Central London Jun 13 64.77% 127,813 135 Claims to handle over £1m of employee shopping every day and save them £3m each month
51 MetaPackE-commerce software developer Central London Mar 14 64.49% *15,574 192 Aims to eliminate the need to wait in for deliveries
52 Qube GBCommunications services provider Scottish Borders Mar 14 63.23% *25,979 500 Sales have been boosted by the government’s pledge to improve broadband speeds
53 GBM DigitalIT consultancy Manchester Dec 13 62.96% 17,774 35 Customers range from schools to JD Sports
54 Camlin GroupTransport power systems developer County Antrim Dec 13 62.10% *16,305 164 Is supplying power control systems for London's Crossrail, Europe's largest infrastructure project
55 Next Generation DataDatacentre operator Surrey Dec 13 61.61% 8,023 33 Terrorist attacks near previous offices convinced the founders to establish secure data centres
56 CrimtanDigital advertising technology developer Central London Dec 13 61.52% *6,098 65 International sales account for 60% of revenue
57 EDM GroupInformation management services Central London Mar 14 61.14% *67,107 1,135 Has made four acquisitions since 2007 including one in America
58 moneyPrice comparison website Gloucestershire Oct 13 60.69% *16,365 20 Chief executive Chris Morling taught himself to code websites in order to start the business
59 OneComTelecoms services provider Hampshire Dec 13 60.30% *43,775 275 Manages more than 200,000 mobile phone contracts
60 CMO SoftwareHSE & compliance software developer Central London Sep 13 58.77% *6,120 90 Counts Network Rail, Glencore and Shell among its customers
61 GGMRDigital marketing agency Wiltshire Oct 13 58.02% *6,531 22 Has worked for Prince William and the Duchess of Cambridge
62 MasternautVehicle tracking software developer Buckinghamshire Dec 13 57.59% *69,734 500 Companies using Masternaut's technology can save up to 15% on their fuel bills
63 essensysCloud service provider Central London Jul 13 57.34% *5,350 24 Its Jeff software automated more than 1m IT helpdesk requests in 2013
64 EmpoweredIT services provider Bedfordshire May 14 57.28% *8,767 70 Acquired three of its rivals in the first half of 2014
65 EmoderationSocial media management agency Central London Mar 13 55.37% 6,248 435 Manages social media activity for MTV and the Oprah Winfrey Network
66 Nomad DigitalTransport communications provider Newcastle Jun 13 54.16% 31,565 191 Working with T-Mobile on biggest roll-out of wi-fi on trains in eastern Europe
67 Nostrum GroupFinancial software developer Harrogate Dec 13 53.73% 7,001 57 Automates the process of providing credit to customers
68 SecretSales.comFlash sales website Central London Dec 13 52.15% *18,163 74 Helps prestigious brands sell off excess stock
69 Click TravelTravel management system developer Birmingham Mar 14 51.91% *66,420 104 Won the up-to-£800m contract to manage travel for UK local authorities
70 DisplaydataElectronic shelf-labelling provider Berkshire Mar 14 51.75% *14,019 62 Says its software can update 700m price labels worldwide in 17 seconds
71 CR360Software developer Cambridge Jun 14 51.75% *7,666 118 Helps Marks & Spencer to audit its supply chain
72 Aspire Technology SolutionsData services provider Gateshead Feb 14 51.58% *6,188 51 Manages data and telecoms services for Sunderland Football Club
73 AcademiaEducational IT consultancy North London Jun 13 50.38% 37,159 78 Its proprietary ordering software dovetails with customers’ procurement systems
74 HighQCloud collaboration software developer Central London Apr 14 50.38% *5,527 120 Says its customers include 45% of the top 100 UK law firms
75 EisonManaged network services Cheshire Oct 13 50.26% 5,788 27 Says it has a 98% customer retention rate
76 Inspired Thinking GroupMarketing technology provider Birmingham Aug 13 49.81% 43,254 218 Followed key client Pret A Manger to America
77 InoappsIT consultancy Aberdeen Jul 13 49.63% 16,750 200 Opened an office in Malaysia with further expansion planned in Europe and the US
78 VermilionFinancial software developer Central London Mar 14 48.41% *5,569 43 The company is going for growth in the Asia Pacific region with a new office in Singapore
79 ZopaPeer-to-peer lending Central London Dec 13 47.16% *5,378 65 Says it has helped to lend more than £600m to UK consumers
80 PurdicomWireless network provider Oxfordshire Dec 13 46.35% *12,520 33 Schools including Eton, Harrow and Sherborne use this company's wi-fi hardware
81 The Test PeopleSoftware testing provider Leeds Mar 14 45.81% *6,954 104 Has developed a graduate academy to train new testers
82 XexecReward programmes administrator Northwest London Nov 13 45.48% *24,214 40 Says 2m end-users make £150m of transactions through Xexec sites every year
83 MOFILMCrowdsourcing advertising agency Central London Sep 13 45.39% *†7,896 47 Recently won a Cannes 'Silver Lion' for its Cornetto Cupidity campaign
84 Condeco SoftwareWorkplace management software Central London May 14 44.62% *10,154 152 Invests £2m a year in research and development
85 Core GroupTelecoms services provider Central London Jun 13 44.42% 20,665 145 Partners include O2, EE, 3, Network Rail and Siemens
86 ReevooConsumer review software developer Central London Mar 14 44.41% *5,378 75 Publishes all reviews, good and bad, from real customers
87 Seven Technologies GroupSecurity technology developer County Antrim May 13 43.74% *†10,039 82 In June 2013 it boosted its international footprint with the acquisition of AIM-listed Datong
88 TranslateMediaTranslation services provider Central London Mar 14 43.21% *8,812 93 This translation services company uses its own proprietary software to service its clients
89 Marine Specialised TechnologyBespoke boat designer Liverpool Sep 13 42.91% 14,445 92 More than 90% of the specialised craft it makes are exported
90 MobicaSoftware engineer and tester Cheshire Dec 13 42.62% *21,300 530 Its technology is integrated into a range of devices including mobile phones and smart TVs
91 Leisure Pass GroupTourism smartcard developer Central London Dec 13 42.61% *53,375 15 2m visitors have used this firm's smartcards to get into more than 60 attractions in London
92 IESASupply chain manager Warrington Mar 14 42.57% *143,000 300 Promises 11% saving on non-core supplies with just one invoice to pay
93 ustwoDigital product studio Central London Dec 13 42.56% *15,081 150 Its puzzle game Monument Valley won the Apple Design Award
94 Rittman Mead ConsultingIT consultancy Brighton Dec 13 42.32% 8,093 56 Runs annual Oracle business intelligence conferences in Brighton and Atlanta
95 4SLData-backup services provider Central London Mar 14 42.08% *7,666 70 Says its largest data back-up customer has 8,000 servers operating across 10 time zones
96 PeriscopixDigital marketing agency Central London Mar 14 41.89% *7,144 86 The two founders started the company by investing £1,000 each
97 Ikon ScienceOil & gas software developer Southwest London Mar 13 41.58% 21,131 220 Is expanding into high-resolution geological simulation for the energy sector
98 FluidataInternet services provider Central London Mar 14 41.25% *14,269 60 Aspires to become the 'national grid' of data networks
99 KeytreeDigital IT services Central London Aug 13 41.25% 11,665 120 Has designed and built a virtual reality headset prototype
100 AvectoIT security software developer Cheshire Jun 14 40.73% *8,447 97 Claims 1.5m PCs in Fortune 100 companies use Avecto’s technology

* supplied by company  † annualised figure