Rank Company Location Year end Annual sales rise over 3 years Latest sales £000s Staff Comment
1 OptosRetinal scanning developer Dunfermline 2002 319.54% 3,682 90 Son's blindness led father to design new eye scanning technique
2 TrayportTrading software developer SE London 2002 286.12% 3,087 17 Company says that 2,700 trading screens worldwide use its software
3 InvestisWebsite technology developer Central London 2002 268.32% 2,078 37 Claims that 42 of the FTSE 100 companies are customers
4 KVSEmail storage manager Berkshire 2002 238.91% 8,149 94 Software helped client discover drug-dealing employee
5 IRISYSInfrared systems maker Northamptonshire 2002 230.39% 1,374 43 Infrared sensors screened travellers for fever during SARS outbreak
6 Empower InteractiveWireless messaging provider Central London 2002 221.18% 1,555 47 Technology used to play 'Who Wants To Be A Millionaire?' on mobile phones
7 Pinnacle TelecomTelecoms services provider West Lothian 2002 185.83% 2,736 24 Co-founder left BUPA to set up telecoms consultancy
8 ComplinetCompliance software developer SW London 2002 182.05% 2,488 71 Software helps banks check their client lists for potential terrorists
9 Pole Star Space ApplicationsMaritime communications provider Central London 2002 181.33% 1,192 22 Has helped fit anti-piracy panic buttons to 5,000 ships worldwide
10 Molecular ProfilesPharmaceutical research laboratory Nottingham 2002 181.18% 1,262 12 Conducted drug testing for AstraZeneca, helping it to enforce patents
11 intYInternet services developer Bristol 2002 175.16% 2,281 35 Manages internet security for Tottenham Hotspur and Hereford Cathedral
12 Astex TherapeuticsDrug developer Cambridge 2002 172.96% 1,414 85 Deal with AstraZeneca could earn company up to £25m
13 AbcamOnline antibodies supplier Cambridge 2002 169.51% 1,804 16 Sells 5,000 antibodies online for the human genome project
14 DowcarterDigital marketing consultant Edinburgh 2002 159.70% 2,206 39 Helps the likes of HBOS and Tesco with online marketing
15 Allserve SystemsSoftware developer Ascot 2002 158.84% 54,085 114 Designed payroll and security pass systems for Shell
16 VoxarMedical software developer Edinburgh 2002 152.25% †3,651 72 Computer-game technology adapted for medical use
17 IPTConsumer data collector SW London 2002 142.97% 5,274 54 Runs a marketing database containing 2.4 million email addresses
18 CSRWireless chip developer Cambridge 2002 140.16% 17,163 175 Has raised £53m of funding for Bluetooth chip designs
19 RedEyeE-marketing services provider Crewe 2002 138.40% 1,179 26 Founder posed naked for Cosmopolitan to raise company profile
20 Cambridge Positioning SystemsLocation software developer Cambridge 2002 137.41% 4,013 90 Cambridge University don raised £20m for phone tracking software
21 ComtecTravel software developer South Wales 2002 135.74% *5,683 59 Develops travel software for Thomas Cook, Lunn Poly and Opodo
22 InclarityTelecoms services provider North London 2002 128.43% 8,208 32 Claims to offer broadband phone calls at half the price of BT land lines
23 Advanced Transport SystemsTransport system supplier Bristol 2002 127.20% 1,287 14 Founder previously worked at NASA and Bristol University
24 TrigenixMobile software developer Cambridge 2002 120.22% 3,067 54 Software allows mobile phones to display recently scored goals
25 IXEuropeData centre provider East London 2002 117.46% 7,772 96 Uses bullet-proof glass and air locks to protect clients' servers
26 Source SoftwareFinancial software developer South Wales 2002 115.11% 5,720 41 Says 2,500 brokers use its software to compare mortgage quotes
27 MultimapOnline map provider Central London 2002 114.43% *2,599 31 Claims to provide 4m maps every day over the internet
28 Digital UnionE-business software developer Guildford 2002 113.34% 2,463 32 Claims its online auction saved Tesco 35% on transport contracts
29 Omitec GroupElectronic equipment maker Wiltshire 2002 112.33% 18,938 180 Supplies MG Rover with testing system for its sports cars
30 MotivanoApplication services provider West London 2002 112.21% *2,980 27 Serial entrepreneur founded company after selling his telecoms business
31 MessageLabs GroupManaged technology provider Gloucestershire 2002 112.04% 29,538 276 Claims its software protects government email from spam and viruses
32 Systems AbilityIT services provider Surrey 2002 110.96% 1,026 14 Manages software for Johnson & Johnson and Argos
33 Nimbus PartnersBusiness software developer Hampshire 2002 108.45% 1,314 30 Designed a patient record system for the NHS
34 Silver Software ConsultantsTransport software developer Wiltshire 2002 106.70% 2,083 50 Develops software for aircraft and railway signals
35 Fasthosts InternetInternet services provider Gloucester 2002 105.95% *7,640 57 Teenagers’ web-hosting start-up now has more than 400,000 users
36 CeloxicaMicrochip software developer Oxfordshire 2002 99.43% 2,272 84 Oxford University spin-out raises £40m venture capital
37 dnsIT security consultancy Edinburgh 2002 98.83% 1,990 28 Founders formulate business plan during daily three-hour commute
38 LaganGovernment software developer Belfast 2002 98.24% 1,884 42 Claims it has won business with 33 local councils since 2001
39 VocalitySatellite equipment designer Surrey 2002 98.03% 2,177 13 Technology enabled journalists to report live from the field during Iraq war
40 AvellinoData software developer Berkshire 2002 95.66% 5,632 40 Claims Abbey National saved £15m by using its data-checking software
41 Inweb NetworksTelecoms services provider Surrey 2002 94.21% 2,415 9 Former Saatchi & Saatchi designer founded telecoms company
42 Listening CompanyCall-centre software provider West London 2002 93.39% 13,743 386 Provides customer relations software to Volkswagen, BUPA and Oxfam
43 NetshiftElectronic kiosk developer Newbury 2002 93.20% *1,782 42 Designed touch-screen computer system for the National Gallery
44 EurocallTelecoms services provider Manchester 2002 89.78% 52,327 92 Serial entrepreneurs started company with £3m of own funds
45 Enteraction TVBroadband services provider SW London 2002 85.95% 3,692 38 Produces branded TV channels for Thomas Cook and Best Direct
46 Zen InternetInternet services provider Rochdale 2002 83.60% 3,502 37 Company conceived in a pub after brother said ‘internet will be a hit’
47 Adastra SoftwareHealthcare software developer Ashford 2002 83.27% 3,820 56 Software handles up to 7m out-of-hours patient calls a year
48 RidgianFinancial software developer Birmingham 2002 83.25% *1,531 18 Working with Birmingham City Football Club on a new ticketing system
49 WesticaWireless communications provider Paisley 2002 80.94% 1,229 18 Develops specialised radio products for the military and emergency services
50 AttendaIT services provider West London 2002 80.14% 8,961 112 Has raised £29m in funding from venture capitalists
51 ActixTelecoms software developer West London 2002 78.14% 8,920 65 Software used by 200 mobile operators and systems vendors worldwide
52 ClinPhoneClinical trials processor Nottingham 2002 77.44% 15,254 198 Processes clinical trial data from 90 countries in 70 languages
53 AspectiveE-business systems integrator West London 2002 76.97% 19,188 169 Signed five-year deal worth £18m with the Law Society last year
54 Sift GroupWebsite community developer Bristol 2002 75.99% 2,820 78 Founders claim to have declined £85m offer from Freeserve in 2000
55 ANS GroupHosting services provider Manchester 2002 75.53% 5,185 44 Started with £100,000 of contracts from founder's former employer
56 GamCom SolutionsE-business software developer NW London 2002 74.99% 1,442 21 Helped mortgage lender automate online application process
57 ProphilianDrug delivery researcher Nottingham 2002 74.52% 8,976 104 Has used over 10,000 volunteers in clinical trials over 13 years
58 FastNet InternationalInternet services provider Brighton 2002 74.00% 1,023 11 Won association award in February for Best Small Business ISP
59 Integrated Communications for BusinessTelecoms services provider Reading 2002 73.27% 10,275 54 Founded with £150,000 investment from business angel
60 KW InternationalTrading software developer SW London 2002 72.88% 11,453 145 Software helps electricity companies decide how much power to generate
61 ETTTelecoms services integrator Central London 2002 72.58% 13,099 66 Helps build telecoms networks for global giants such as Ford
62 NallatechComputing systems designer Glasgow 2002 71.55% 1,636 45 Claims to reduce search times for diseases in the human genome
63 Ubiquity SoftwareTelecoms software developer Newport 2002 70.53% 2,037 100 Raised £26m from venture capital and corporate investors
63 Princeton ConsultingIT systems integrator Slough 2002 70.53% 9,164 93 Software simplifies phone call transfers for Middlesbrough Council
65 Neural TechnologiesArtificial intelligence software developer Hampshire 2002 70.47% 3,537 35 Artificial-intelligence software helps detect credit-card fraud for Visa
66 Nonlinear DynamicsBiotech software developer Newcastle 2002 70.37% 3,913 55 Claims to spend 40% of sales on research and development
67 Essential Network ServicesIT network consultancy SE London 2002 70.27% *2,142 26 Manages networks and telecoms for Accenture and Barings
68 Cad-CaptureDocument scanning agency Blackburn 2002 70.24% 2,787 39 Scanned a container load of documents from a Shell plant in Nigeria
69 Cable TelecomTelecoms services provider Central London 2002 70.22% 12,038 17 Provides telecoms services to customers such as Burberry and McDonald's
70 Mistral Internet GroupInternet service provider Brighton 2002 69.39% *†5,763 45 Offers web hosting for Microsoft, Sony and Bacardi Breezer
71 SynetrixNetwork technology provider Staffordshire 2002 68.17% 14,247 27 Selected as one of the government's preferred broadband suppliers
72 InvocomTelecoms network integrator Reading 2002 67.72% 2,004 10 Offers telecoms consulting to BT and Cable & Wireless
73 Legend InternetInternet services provider Bradford 2002 66.86% 1,963 29 Has converted old wool warehouse into a modern data warehouse
74 EDW TechnologyRetail software developer Milton Keynes 2002 65.81% 2,791 31 New Zealand office allows 24-hour customer service
75 Paragon ConsultingBusiness software consultancy West London 2002 64.73% 1,889 18 Provides financial analysis software to Invensys and AstraZeneca
76 AmplefutureMobile software developer Central London 2002 64.26% 16,119 85 Provided interactive texting service for Big Brother 4
77 EndXCasino software developer Oldham 2002 63.37% 1,766 18 Claims to sell its software to more than 85% of British casinos
78 Eiger SystemsPayment software developer Rugby 2002 61.79% 2,859 25 Software helps internet bank Egg validate customer details
79 Wolfson MicroelectronicsMicroelectronics maker Edinburgh 2002 60.95% 22,416 86 Designs semiconductors used in Dell PDAs and Microsoft’s Xbox
80 Moneysupermarket.comFinancial website operator Wales 2002 59.33% 13,608 113 Website receives 10,000 credit-card and loan applications daily
81 Babel MediaGames services provider Brighton 2002 59.32% 1,748 39 Translates video games into local languages for Sega and Microsoft
82 1EEnterprise software developer West London 2002 58.84% 2,397 26 Claims software saves up to £100 in electricity per PC a year
83 Micron ResearchPharmaceutical software developer Cambridge 2002 57.87% †6,327 8 Software allows drug studies to be observed worldwide over the internet
84 ImergeAudio-video systems developer Cambridge 2002 57.41% 2,000 49 Internet-linked audio system allows playback throughout the home
85 CDC SolutionsDocumentation software developer Wiltshire 2002 57.29% 7,464 83 Software manages production of documents up to 1m pages long
86 Anvil SoftwareTrading software developer Central London 2002 56.16% 4,597 55 Founded by four computer scientists from University College, London
87 SirocomTelecoms services provider SW London 2002 55.86% 8,866 40 Linked Abbey National's 3,000 roaming employees with head office
88 Capital CaptureDocument scanning agency Central London 2002 55.80% *1,231 24 Scans 4,000 pieces of post a day for the insurance giant Aon
89 BOOT ComputersTrading software developer Cheshire 2002 55.58% 2,668 28 Designs bespoke software for market-maker Winterflood Securities
90 SafeStone TechnologiesIT security provider Buckinghamshire 2002 54.72% 3,563 69 Protects servers from hackers at Kleinwort Benson's Channel Island branch
91 Rule FinancialBusiness and IT consultancy Central London 2002 53.46% *6,078 27 Develops financial software for ABN Amro, Deutsche Bank and Merrill Lynch
92 edNETInternet services provider Edinburgh 2002 53.45% 1,698 25 Father helped medical-student son start business at university
93 PIPEX InternetInternet services provider Hertfordshire 2002 53.09% 21,690 56 Claims to be Britain's first commercial internet service provider
94 ePulseFinancial software developer Central London 2002 52.64% 1,711 23 Software keeps audit trail for trades done by instant messaging
95 Oakleigh ConsultingIT consultancy Manchester 2002 51.13% 3,910 30 Claims to have saved government £700,000 on IT project
96 Alternative NetworksTelecoms systems integrator SW London 2002 50.13% 26,454 174 Provides telecoms services for 3,000 small firms
97 Surrey Satellite TechnologySmall satellite maker Guildford 2002 50.05% 12,244 130 Helped launch satellite using an intercontinental missile
98 Penn PharmaPharmaceutical services provider South Wales 2002 49.28% 12,811 167 Biotech firm founded by £12m management buy-out
99 Yorktest LaboratoriesAllergy test developer York 2002 48.48% †1,751 33 Chief executive awarded MBE in January for services to industry
100 Fifth Dimension SystemsE-business systems integrator Cardiff 2002 48.29% 2,715 38 Claims to have signed 70 new customers in the past year

* supplied by company   annualised figure