Permanent Carrier Pre-Selection is now available from BT, which means that's smartboxes and indirect access codes may be ignored because an Other Licensed Operator can now arrange with BT for all local, national, international NTS, mobile, page and personal calls to be 'diverted' without needing to dial any extra codes (different types of call may be routed to different OLOs) . If CPS is set-up, indirect codes may still be dialled to use alternate operators or to use BT (code 1280).
CPS can be supplied on single or multiline PSTN or ISDN lines.
This list is compiled from information published by Ofcom and has not been checked by Magenta Systems.
A CPS guide is available from Ofcom.
| Communications Provider | Communications Provider | Contact Address | Telephone |
| (aq) Ltd T/A aql | aql | 13-15 Hunslet Road Leeds LS10 1JQ | 0870 744 9227 |
| 08 Numbers Ltd | 08 Numbers Ltd | 100 Mount Pleasant Westerham KENT TN16 3TR | 0800 848 800 |
| 1 Telecom Ltd | |||
| 10 Telecom Ltd | |||
| 118 Group Ltd | 118 Group Ltd | 87 Waterhouse Business Centre Cromar Way Chelmsford Essex CM1 2QE | 01245 392172 |
| 121 Comms Ltd | 121 Comms Ltd | Newham Farm 5 Wales Street Rothwell Northants NN14 6JL | 08452 720 121 |
| 123Telecom Ltd | 123Telecom | 305 Vale Enterprise Centre Hayes Road, Sully Vale of Glamorgan CF64 5SY | 0870 871 0123 |
| 1st Advance Ltd | |||
| 1st Call Communications Ltd | 1st Call Com Ltd | Station House 6a Station Road Eckington Sheffield South Yorkshire S21 4FX | 01246 439 800 |
| 1st Connect Group Ltd | 1st Connect Group Ltd | 46 Cobham Road Ferndown Industrial Estate Dorset BH21 7QG | 01202 850 000 |
| 21ip Ltd | 21ip | 8 North Hills Brill Aylesbury Bucks HP18 9TH | 01844-239750 |
| 21st Century Telecom.com Ltd | 21st Century Telecom.com Ltd | 23 Gaolgate Street Stafford ST16 2NT | 0870 777 2121 |
| 24 by 7 Communications Ltd | |||
| 24Talk | 24Talk | Unit 25, City Business Centre 6 Brighton Road Horsham West Sussex RH13 5BB | 0845 345 2889 |
| 360 Solutions (UK) Ltd | 360 Solutions Network Services | 360 House Newborough Road Needwood DE13 9PD | 0845 223 6360 |
| 360CRM Ltd | 360CRM | 2 Cockburn Place Irvine KA11 5DA | 01294 316504 |
| 365 Telecom Ltd | |||
| 3C Telecom | 3C Telecom | 67 Manor Road Romford Essex RM1 2RD | 0870 750 7088 |
| 3g Comms Ltd | 3g Landline | Cuckoo Wharf 427 Lichfield Road Aston, Birmingham B6 7SS | 0121 328 8444 |
| 3Mi Ltd | |||
| 3R Net Ltd | 3RNet | PO Box 42599 Wapping High Street London E1W 3LA | 0870 1748570 |
| 4 Business Calls Ltd | 4 Business Calls Ltd | 282 Heywood Old Road Middleton Manchester M24 4QG | 0807 300 4299 |
| 4 Networks Ltd | 4 Networks Ltd | 95 Manchester Road Rochdale, Lancashire OL11 4JG | 0870 906 0066 |
| 4Com Ltd | |||
| 4most Solutions LLP | 4most Solutions LLP | Boxhill Cottage Dorking Surrey RH5 6BS | 0870 111 0700 |
| 4Net Technologies Ltd | 4Net Technologies Ltd | Maclaren House Talbot Road Manchester M32 0FP | 0845 055 6366 |
| 4Sight UK Ltd | Freeman Telecom | 8 Anker Lane Fareham Hampshire PO14 3HF | 07866 564 021 |
| 4SQR | 4SQR | 92 Margate Road Herne Bay KENT CT6 7BJ | 0870 2247424 |
| 4tech Connect Ltd | 4tech Connect Ltd | 38 Morgan Way Bowthorpe Industrial Estate Norwich , Norfolk NR5 9JJ | 0870 167 2265 |
| 4tel Communications Ltd | 4tel Connect | Penstraze Business Centre Truro TR4 8PN | 0800 505 3210 |
| 4theNet Internet Ltd | 4theNET Call | The Old Bakery 61 High Street Rottingdean BN2 7HE | 0870 740 1619 |
| 4ward Communications | 4ward Communications | Unit G35 Hastingwood Trading Estate Harbet Road LONDON N18 3HT | 08700 411 005 |
| 5 Rings Telecom Ltd | 5 Rings Telecom Ltd | Findale House 151 Findon Road Worthing West Sussex BN14 0BQ | 0845 680 1555 |
| 5miles Communications Ltd | 5miles Communications Ltd | 67 London Road Bognor Regis West Sussex PO21 1DF | 08452 249 041 |
| 6 Communications Ltd | 6Comms | 6 Communications Ltd 2nd Floor 145-157 St John Street London EC1V 4PY | 08456 525603 |
| Abacus Lloyd Ltd | Abacus Lloyd Communications | Daws House 33-35 Daws Lane London NW7 4SD | 08444 821 482 |
| Abjak Ltd | Abjak Ltd | Unit 1a, Sovereign House Bramhall Village Centre Bramhall Stockport SK7 1BD | 07710 695006 |
| Abrient Ltd | Abrient Ltd | The Old Smithy Bath Road Oakhill Somerset BA3 5AQ | 01749 841525 |
| Absolute Numbers Ltd | Absolute Numbers Ltd | Forum House Stirling Road Chichester West Sussex PO19 7DN | 08454 501910 |
| Abtec Services UK Ltd | Abtec Communications | Quarry House Mill Lane Uckfield, East Sussex TN22 5AA | 0870 777 7030 |
| Abycom Ltd | Abycom Ltd | Daisy House Lindread Road Business Park Nelson Lancs BB9 5SR | 08456 777888 |
| Accent Telecom UK Ltd | Accent Telecom UK Ltd | PO Box 328 Witney OX28 1ZR | 0870 950 1630 |
| Access Business Communications Ltd | abc | 72 Elderslie Street Glasgow G3 7AL | 0845 373 3622 |
| Access Telecommunications Retail Ltd | |||
| ACN European Services Ltd | ACN | ACN European Services Ltd AMS/AMS/136762/AUK PO. Box 66 Hounslow TW5 9RT | 0800 331 60 07 |
| Acomys Ltd | Acomys Ltd | 2 Church Street Wiveliscombe Taunton TA4 2LR | 01984 678 150 |
| ACR Networks Ltd | |||
| ACT (Comms) Ltd | ACT | Hexagon House 71 Lower Road Kenley Surrey CR8 5NH | 08707 74 75 76 |
| Actimax PLC | Actimax plc | 1 Yardley Business Park Luckyn Lane Basildon Essex SS14 3GL | 01268 243 903 |
| Activ Communications | |||
| Active Comm.Solutions | |||
| Activtelecom Ltd | Activtelecom Ltd | 3 Atley Way North Nelson Industrial Est Cramlington Northumberland NE23 1WA | 0870 7871161 |
| ADA Networks Ltd | ADA StreamNET | 3 Mill Court Mill Lane Newbury Berks RG14 5RE | 01635 523131 |
| Adam Phones Ltd | |||
| adapt | IP Voice | 142-148 Goswell Road London EC1V 7DU | 020 7324 3700 |
| Add Communications Ltd | Yourtel | 27 Fishergate Hill Preston PR1 8JB | 0845 225 6006 |
| AdEPT Telecom | AdEPT Telecom | Customer Service 77 Mount Ephraim Tunbridge Wells, Kent TN4 8BS | 0870 190 9100 |
| AdEPT Telecom | Adept Telecom-Admiral | 77 Mount Ephraim Tunbridge Weels Kent TN4 8BS | 0870 190 9125 |
| ADK Communications | ADK Communications Ltd | 7a The Maltings Railway Place Hertford Herts SG13 7JT | 0845 345 9212 |
| Admiral Managed Networks | Admiral Managed Networks Ltd | Victory House Chobham Street Luton Beds LU1 3BS | 0870 330 7500 |
| Admiral Voice and Data Ltd | Admiral Voice and Data Ltd | Victory House Chobham Street Luton Bedfordshire LU1 3BS | 01582 557 925 |
| Adodo Communications Ltd | Adodo | The Howitt Building Lenton Boulevard Nottingham NG7 2BG | 0800 092 1471 |
| ADP Dealer Services UK Ltd | ADP Dealer Services Ltd | Herongate Charnham Park Hungerford RG17 0YU | 0845 30 31 300 |
| ADP Dealer Services UK Ltd | ADP Talk | Herongate Charnham Park Hungerford Berkshire RG17 0YU | 01635 523456 |
| Adtrak Services Ltd | Adtrak Services Ltd | Wayside 1 Hallfields Edwalton Nottingham NG12 4AA | 0800 542 0116 |
| Advance Network Services Ltd | |||
| Advancz Telecommunications Ltd | Advancz | 60 Bagley Lane Farsley Leeds LS28 5LY | 0870 0666 308 |
| Aerofone (UK) Ltd | Aerofone | Aerofone (UK) Limited Manton Lane Bedford MK41 7TL | 0845 330 7700 |
| Affinicom Ltd | Affinicom Ltd | Leeds Farm House Poplar Road Wittersham KENT TN30 7NT | 01797 270 441 |
| Affiniti Integrated Solutions Ltd | Affiniti | Customer Service Front Desk Melbourne House Brandy Carr Road Wrenthorpe, Wakefield WF2 0UG | 0800 138 48 58 |
| Affordable Digital Solutions Ltd | Affordable Digital Solutions Ltd | Tong Hall Tong Village Bradford BD4 ORR | 0870 6098041 |
| Afrigate Ltd | 21st Century Telecoms Ltd | Old Dominion House Gravel Hill Henley-on-Thames Oxfordshire RH9 2EG | 01491 637857 |
| Aggregated Telecom Ltd | 8elCPS | Aggregated Telecom Prophecy House 87 London Street Reading RG1 4QA | 0118 955 0800 |
| AIC Telecom (UK) Ltd | AIC Telecom (UK) Ltd | 1st Floor 12-13 Little Newport Street London WC2H 7JJ | 0207 437 7123 |
| Air Net Services Ltd | Air Net Services Ltd | 62 St Philips Road Keyingham Hull HU12 9TD | 0800 916 8570 |
| Airmart Ltd | Cortel | 32 Shoreditch High Street London E1 6PG | 020 7247 0101 |
| Airphone Telecom Ltd | |||
| Airtime Express Ltd | |||
| AJ Business Solutions Ltd | AJ Business Solutions | 16 Browning Street Stafford ST16 3AX | 08707 518 900 |
| Alban Telecom Ltd | Alban Telecom Ltd | The John Dickinson Enterprise Centre London Road Hemel Hempstead Hertfordshire HP3 9QU | 0845 0654 321 |
| Albion Computers Plc | Albion Computers Plc | 112 Strand London WC2R 0AG | 020 7212 9090 |
| Alcami Business Service Ltd | |||
| Alfred Ashley Technical Services Ltd | Alfred Ashley Technical Services Ltd | (Business Phone Systems) 38 High Street Northwood Middlesex HA6 1BN | 08708 711 003 |
| Allcomm Communications Ltd | Allcomm Communications Ltd | 8-10 Compton Road Wolverhampton London WV3 9PH | 0845 8506107 |
| Allcooper Ltd | Allcooper Ltd | Connect Division 7 Hucclecote Road Gloucester GL3 3TQ | 01452 565 758 |
| Allenwood Enterprises Ltd. | smalltalk communications | Bourne House Milbourne Street Carlisle Cumbria CA2 5XF | 01228 635554 |
| Alliance Bell Communications Ltd | Alliance Bell Communications Ltd | BCR House Bredbury Business Park Stockport Chesire SK6 2SN | 08456 730 011 |
| Alliance Communication Solution Ltd | Alliance Communication Solution Ltd | Milton Heath House Westcroft Road Dorking, Surrey RH4 3NB | 0870 770 7370 |
| Alliance Communications Ltd | Alliance Communications Ltd (ACL) | Towerhurst Church Road Leigh Woods Bristol BS8 3PG | 0870 300 2022 |
| Alliance Communications Ltd | Tube Telecom | Towerhurst Church Road Leigh Woods Bristol BS8 3PG | 0870 300 2022 |
| Allied Network Services Ltd | Thus Plc | 1-2 Berkeley Square 99 Berkeley Street Glasgow G3 7HR | 0141 567 1234 |
| Alpha Business Communications Ltd | AlphaNet | Network Centre High Carr Business Park Newcastle-Under-Lyme Staffordshire ST5 7XE | 01782 576 000 |
| Alpha Overseas International Telecommunications Services Ltd (AOITSL) | Alpha Communications | 75 route de Longwy LU 8080 Bertrange Luxembourg | 0845 085 0250 |
| Alphatalk Ltd | |||
| Alternative Networks | Alternative Networks Ltd | Chatfield Court 56 Chatfield Road London SW11 3UL | 0800 816 8866 |
| AlwaysOn Ltd | AlwaysOn | 1 Napier Court Napier Road Reading RG1 8BW | 0845 241 8300 |
| AM Telecom Ltd | AM Telecom | Radclyffe House 66-68 Hagley Road Birmingham B16 8PF | 0121 456 3273 |
| Amcall Communications Ltd | |||
| Amerada Telecom | |||
| Amillan Ltd | Amillan Ltd | Connection House 3 The Parkway Centre Heneage Street Birmingham | 0121 260 8100 |
| Ampito Ltd | Matelco | 1 Farnham Road Guildford Surrey GU2 4RG | 0870 352 1004 |
| Andrews & Arnold Ltd | AAISP | Enterprise Court Downmill Road Bracknell RG12 1QS | 01344 400 009 |
| Angel Networks Ltd | |||
| Anglia Telecom Centres Plc | |||
| Anglo Telecom | |||
| ANH COMMUNICATIONS LTD | |||
| Annodata Business Communications | |||
| AOL Europe Services SARL | AOL | IDA Business Park Cork Road Waterford Ireland | 0800 376 5432 |
| Aonix (UK) Ltd | Aonix Connect Services | Select House Popes Lane Oldbury West Midlands B69 4PA | |
| Appleacre Communications | Rocket Connect | Communications House 3-5 Aleandra Terrace Alexandra Road Alderhot GU11 3HU | 01252 669 220 |
| Applegarth Communications Ltd | Applegarth Communications Ltd | 375 Meanwood Road Leeds LS7 2LL | 0113 2441442 |
| Applica | applicahome | Willowbank House 84 Station Rd Marlow Bucks SL7 1NX | 0870 164 993 |
| Applied Voice and Data Solutions | Applied Voice and Data Solutions | Cathedral House 23/31 Waring Street Belfast BT1 2DX | 028 9043 6618 |
| Applinet Plc | Applinet Network Services | Unit 14, Thatcham Business Village Colthrop Way Thatcham Berkshire RG19 4LW | 01635 848900 |
| APT - Information & Communication Technologies Ltd | APT-ict | 1st Floor Offices, Haslemere Stn Lower Street Haslemere Surrey GU27 2PE | 08445 449 450 |
| Ardencom Ltd | Ardencom Ltd | Wellington House Starley Way Birmingham Int. Park Solihull B37 7HE | 0870 264 6465 |
| Arkadin UK Ltd | ARKADIN UK LTD | 26-28 Hammersmith Grove LONDON W6 7JA | 020 8742 6398 |
| Arkenis UK Ltd | Arkenis-Talk-Time | Arkenis House Brook Way Leatherhead Surrey KT24 7NA | 01372 204700 |
| Armstrong Bell Ltd | Armstrong Bell Ltd | Suite 1, Winwood Court Norton Road Stourbridge West Midlands DY8 2AE | 0845 0719444 |
| Armstrong Communications Plc | Armstrong Communications Plc | 4 Cody Court Kansas Avenue Salford Manchester M50 2GE | 0161 868 3003 |
| Arrow Communications Direct Ltd | Arrow Communications Direct Ltd | 102C Bancroft Hitchin Herts SG5 1NB | 01462 441 445 |
| Arrow Mobile Communications Plc | Arrow | Marine House Morton Peto Road Great Yarmouth Norfolk NR31 0LT | 01493 663 132 |
| As-Voip Communications | As-Voip Communications | 20 Fletcher Gate Nottingham NG1 2FZ | 01159 838795 |
| Ashgoal Ltd | Ashgoal Ltd | Unit C, Queens Road Barnet Herts EN5 4DJ | 020 8275 5100 |
| Aspect International Telecoms Ltd | Aspect | Claredon House High Street Stockbridge SO20 6EY | 0845 634 5566 |
| Assure Telecom | Assure Telecom | 131 Stooperdale Avenue Darlington Co Durham DL3 0UD | 08701 903 060 |
| Ast Networks Ltd | AST Networks Ltd | Temple Court, Cathedral Road Cardiff CF11 9HA | 0870 1160110 |
| Aston Barclay UK Ltd | Aston Barclay UK Ltd | 38 Billing Road Northampton NN1 5DQ | 01604 603 066 |
| Astra Connect Services | |||
| Astron Communication & Information Services Ltd | Astron Communication & Information Services Ltd | PO Box 6379 Wimborne BH21 9BN | 0800 376 3113 |
| Astute Communications Ltd | Astute Communications | 323 Wilmslow Road Manchester M14 6NW | 0844 4068 714 |
| AT Communications | |||
| Atlantic Solutions | |||
| Aurora Networks Ltd | Aurora Networks Ltd | 84-85 Long Lane London EC1A 9ET | 0870 410 0910 |
| Aurora UK Ltd | Aurora UK Ltd | Unit 7b Sherwood House Walderslade Centre Chatham Kent ME5 9UD | 01634 672 635 |
| Auto Personnel Ltd T/A Digi-tel Communications | Auto Personnel Ltd T/A Digi-tel Communications | 3 Mews House Princes Lane Muswell Hill London N10 3LU | 020 8444 7333 / 07887 867569 |
| Autovoice Ltd | AUT - Autovoice Ltd | 5 Rectory Lane Breadsall DERBY DE21 5LL | 0845 257 5632 |
| Avandda Ltd | Avandda Ltd | 820 Birchwood Boulevard Birchwood Warrington WA3 7QZ | 01925 250010 |
| Avenue UK Ltd | Southland UK Ltd | 60 Charlotte Road London EC2A 3QT | 020 7729 2857 |
| Avoco UK Ltd | Avoco | Unit 38 Derwentside Business Complex Villa Rental Consett, County Durham DH8 6BP | 0845 241 5500 |
| Avonline plc | |||
| Axamba Ltd | Axamba | 36 Davyhulme Road East Stretford Manchester M32 0DW | 0870 777 5215 |
| Axiom Business Systems Ltd | Axiom Business Systems Ltd | Wardens House 4 Broad Street Stamford Lincolshire PE9 1PB | 01780 484 160 |
| Axis Telecom Ltd | |||
| Azure Telecommunications Ltd | Azure Telecommunications Ltd | No 70, Annexe Four Technology Drive Batley WF17 6ER | 0845 634 1504 |
| Azzurri Communications Ltd | Azzurri Communications Ltd | Azzurri Hous Walsall Business Park Walsall Road, Aldridge West Midlands WS9 0RB | 01922 650111 |
| B-Partners Ltd | Planet-B | 10 Barley Mow Passage Chiswick London W4 4PH | 020 8090 2971 |
| B C Computing Ltd | BCC Group | The Old Rectory Ferrybridge Road Castleford WF10 4JW | 01977 667777 |
| B.C.M. (Transport) Ltd | RHA Telecom | 28 Bouverie Road West Folkestone Kent CT20 2TG | 0870 870 3232 |
| Bandwidth Networks Ltd | BWN Telecom | Unit 16, Universal Marina Sarisbury Green Southampton S031 7ZN | 08700 33 0645 |
| Banner Business Supplies | talk2office | o2o House Bilton Road Kingsland Business Park Basingstoke, Hampshire RG24 8LJ | 0845 129 7230 |
| Barker Telecommunications Ltd | Barker Telecommunications Ltd | Eagle Street Bury New Road Bolton BL2 2BU | 01204 380 002 |
| Barrington Technology Ltd | Barrington Technology Ltd | The Old Barn Cidermill Farm Partridge Lane, Newdigate Surry RH5 5BP | 0870 873 0055 |
| BCAS (UK) Ltd | Intouch4U | Communications House 143 Maidstone Road Rochester Kent ME1 1RR | 0845 468 6824 |
| BDI CCTV Ltd | BDI CCTV Ltd | The Arches Trinity Business Park Fox Way Wakefield, West Yorkshire WF2 8EE | 01924 370900 |
| BDM Voice Ltd | BDM Voice Ltd | The Priory Centre Franklynn Road Haywards Heath West Sussex RH17 5DS | 0845 373 4100 |
| BDR Networks Ltd | |||
| Beagle Communications Ltd | |||
| Beaming Ltd | Beaming Ltd | Innovation Centre Highfield Drive St Leonards On Sea East Sussex TN38 9UH | 0800 027 2656 |
| Beanstalk Telecom Ltd | Beanstalk Telecom Ltd | 100 High Ash Drive Leeds LS17 8RE | 0845 130 5211 |
| Belcom Networks | Belcom Networks | 3 Wellington Park Belfast BT9 6DJ | 0845 270 4411 |
| Bellview Comms Ltd | BellView Comms | 22 Newlands Woods Bardolph Avenue Croydon CR0 9JR | 07734 046654 |
| Benison Communications Ltd | Benison Communications Ltd | The Beeches Station Road Laurencekirk Aberdeenshire AB30 1BE | 01561 377 660 |
| Best 4 Business Communications Ltd | Best 4 Business Communications Ltd | 41 Conway Road Shirley Solihull B90 4RF | 0121 244 0787 |
| Best Communications | Best Communications | 82 Wykeham Street Kirkdale Merseyside L4 1QY | |
| Best Value Providers Ltd | Best Value Providers | 3 Trinity Street Stratford-upon-Avon Warwickshire CV37 6BL | 0871 4 25 27 29 |
| Better Telecom Ltd | Better Telecom Ltd | Unit 5 & 6 Greenline Business Park Wellington Street Burton-On-Trent Staffordshire DE14 2AS | 0845 652 0248 |
| Better Telecoms | Better Telecoms | 121 London Road Knebworth Herts SG3 6EX | 0870 758 2700 |
| Between the Lines Communication Ltd | Between The Lines Communication | Brackenmount House 58 Napier Road Crowthorne RG45 7EL | 0845 450 2100 |
| Bills R Us Ltd | Bills R Us Ltd | Abbey Mill, Station Road Bishops Waltham Southampton Southampton SO32 1GN | 01489 896021 |
| BillSmart Ltd | Bill Smart Ltd | Paragon House Lord Street South Leigh Lancashire WN7 1YB | 0800 096 0202 |
| BIS Ltd | BIS Ltd | The Baltic Exchange 38 St. Mary Axe London EC3A 8BH | 020 7861 9322 |
| BISCIT | Biscit Telecom | 9 Hale Lane Mill Hill London NW7 3NU | 0870 741 9214 |
| BisNet Ltd | BisNet Ltd | 137 Victoria Road Ferndown, Dorset BH22 9HX | 01202 863 246 |
| Black & White Telecom Ltd | Black & White Telecom | PO Box 13 Portrush County Antrim BR56 8WZ | 0870 872 1080 |
| Blackstar Internet Ltd | Blackstar Internet Ltd | Unit 12 Joiners Square Industrial Estate Hampton Street Stoke-On-Trent ST1 3EX | 01782 279 333 |
| Blaze Networks Ltd | Blaze Networks Ltd | Beechfield House Lyme Green Business Park Winterton Way Macclesfield, Cheshire SK11 0LP | 01625 511475 |
| Blizzard Telecom Ltd | Blizzard Telecom ltd | Swan Court Waterhouse Street Hemel Hempstead Hertfordshire HP1 1DS | 0845 8737950 |
| Blue & Red Ltd | Blue & Red Ltd | PO Box 1003 Peterborough PE1 9GG | 0845 603 0603 |
| Blue Diamond Telecommmunications Ltd | Blue Diamond Telecommunications Ltd | Alexander House 106 Pembroke Road Ruislip Middlesex HA4 8NW | 0870 055 4242 |
| Blue Line Communications | Blue Line Communications | Trewen The Street Motcombe Shaftsbury, Dorset SP7 9PF | 01747-854410 |
| Blue Ridge Telecom Systems LLC | |||
| Blue River Telecom LTD | Blue River Telecom LTD | 167 Dunstable Road Luton LU1 1BW | 0844 545 0808 |
| Blue Saffron Ltd | Blue Saffron Ltd | Shakespeare House 168 Lavender Hill Battersea LONDON SW11 5TF | 0870 891 0202 |
| Blue Spot Technologies Ltd | Blue Spot Technologies Ltd | 100 Mount Pleasant Westerham, Kent TN16 3TR | 0870 950 5550 |
| Blue Square Telecoms Ltd | Eurotelecom | 1a Bow Lane London EC4M 9EE | 020 7618 1980 |
| Blue Telecommunications | |||
| Bluebell Telecom Ltd | Bluebell Telecom Ltd | Murlain House Union Street Chester CH1 1QP | 0870 770 8998 |
| BlueBill Ltd | BlueBill Ltd | 57 London Road Enfield Middx EN2 6DU | 020 8370 8370 |
| Bluevolution Ltd | Virtual Carrier Ltd | 61-71 Cornwall Street Birmingham B3 2EE | 0800 015 2772 |
| BON.net Ltd | BON.net | St George's House George's Street Huntingdon Cambridgeshire PE29 3BD | 020 7049 0000 |
| Border Communications | BORDER CALL | LCR Administrator Unit 4, Sweetlake Bus. Village Longden Road Shrewsbury, Shropshire SY3 9EW | 01743 232316 |
| Bourke Telecomunicaoese Servicos LDA | TULIP M | Unit 21, Park Royal Metro Centre Britannia Way London NW10 7PA | 020 8965 8964 |
| Bridgecom Networks Ltd | BRIDGECALL LTD | 2 Alexandra Gate Ffordd Pengam CARDIFF CF24 2SA | 02920 452 525 |
| Bridgwater Communications(South West) Ltd | Bridgwater Communications (South West) Ltd | 57 Eastover Bridgwater Somerset TA6 5AP | 01278 439 300 |
| Brighter Connections | Brighter Connection Ltd | The Continental Suite Hill Top Road Huddersfield HD1 4SD | 01484 467840 |
| Brightview Internet Services | Greenbee Telecom | 9-10 Grafton Street, London W1S 4EN | 020 7665 3000 |
| Brightview Internet Services | Madasafish | 9-10 Grafton Street London W1S 4EN | 020 7665 3000 |
| Britannia Network Services Ltd | Britannia Network Services Ltd | Britannia House 2 Thomas Holden Street Bolton, Lancashire BL1 2QG | 0870 754 5556 |
| Britannic Technologies Ltd | |||
| Britclick Telecom | Britclick Telecom | 40 Huddersfield Road Meltham Huddersfield West Yorkshire HD9 4AG | 0845 1 292922 |
| Britclick Telecom | InterVoip Ltd | 40 Huddersfield Road Meltham Huddersfield West Yorkshire HD9 4AG | 0845 1 292922 |
| Britclick Telecom | Telcoswitch Ltd | 40 Huddersfield Road Meltham Huddersfield West Yorkshire HD9 4AG | 0845 1 292922 |
| British Sky Broadcasting | Sky Talk | PO Box 43 Livingston West Lothian EH54 7DD | 0870 905 9051 |
| Broadtalk Communications Ltd | Broadtalk Communications Ltd | 3-5 Kewus Road Sidcup Kent DA14 4NB | 020 8309 1400 |
| BT | BT Global Services | BT Centre 81 Newgate Street London EC1A 7AJ | 020 7356 5000 |
| BT | BT Retail | BT Centre 81 Newgate Street London EC1A 7AJ | 020 7356 5000 |
| BT | BT Wholesale | BT Centre 81 Newgate Street London EC1A 7AJ | 020 7356 5000 |
| BTT Network Solutions LTD | BTT Nework Solutions | Five Willows Farm Old Thrapston Road Cranford Northampton NN14 4AW | 01536 211100 |
| Budd Communications Ltd | Buddconnect.com | Unit 3 Willcock House Southway Drive Warmley Bristol BS30 5LW | 0845 130 2664 |
| Bulldog Communications Ltd | |||
| Business Efficiency Ltd | Business Efficiency | 8 Robin Crescent London E6 5XA | 07933 361504 |
| Business IT Experts Ltd | "USE MY" | First Floor 21 Kings Avenue Prestatyn Denbigshire LL19 9AA | 01745 886 954 |
| Business Network Services | |||
| Business Network Solutions Ltd | Busniess Network Solutions | 167 Stafford Street Walsall West Midlands WS2 8EA | 01922 471 890 |
| Business Phone Calls Ltd | |||
| Business Serve Plc | |||
| Business Solutions Telecom Ltd | Business Solutions Telecom Ltd | 134 Kennel Lane Gt Burstead Billericay Essex CM11 2SU | 01277 624657 |
| Business Systems (Scotland) | Business Systems (Scotland) | 2 Glenpark Ave Glasgow G46 7JF | 07850 760966 |
| Business Telecom Solutions Ltd | |||
| Business Telenet (UK) Ltd | |||
| Business Telephone Network Services Ltd | Business Telephone Network Services Ltd | 5 Fewster Road Nailsworth Glos GL6 0DH | 01453 833 684 |
| Business Transfer Communications Ltd | |||
| Business VoIP Communications | Business VoIP Communications | 85/12 Hopetoun Street Edinburgh EH7 4NJ | 0845 223 7251 |
| BusinessCall | BusinessCall | Newhaven Pyrford Woods Woking Surrey GU22 8QR | 01932 356 222 |
| Businesswatch UK Telecommunications Ltd | Businesswatch UK Telecommunications Ltd | Unit 6 Orton Enterprise Centre Bakewell Road Orton Southgate Peterborough PE2 6XU | 01733 239 997 |
| Buzz Networks Ltd | Buzz Networks1 | Endeavout II Becketts Wharf Lower Teddington Road Kingston Upon Thames, London KT1 4ER | 020 8614 0700 |
| Bytebak Ltd | Bytebak Communications | 1b South Mill Warwick Mill Warwick bridge Carlisle CA4 8RR | 01228 562 666 |
| C-Net Ltd | C-Net Ltd | 17 Oyster Place Montrose Road Chelmsford Essex CM2 6TX | 01245 451 651 |
| Cable & Wireless Plc | |||
| Cable and Wireless (Energis) | Cable and Wireless (Energis) | Lakeside House Cain Road Waterside Park Bracknell, Berkshire RG12 1XL | 0800 316 1600 |
| Cable Direct Ltd | Cable Direct Ltd | 95 Manchester Road Rochdale, Lancashire OL11 4JG | 0870 906 0066 |
| Cable Direct Ltd | Cable Direct Ltd | Centenary House 95 Manchester Road Rochdale Lancashire OL11 4JG | 0870 906 0066 |
| Cable Telcommunications Ltd | Cable Telecommunications Ltd | 15 The Broadway Woodford Green Essex IG7 6LU | 020 8506 6481 |
| Cable Telecom (GB) Ltd | |||
| Cablestream Ltd | Cablestream Ltd | Glamorgan House Cardiff Gate Business Park Cardiff CF23 8RD | 02920 545 945 |
| Cad-Capture LTD | Airtime | Challenge Way Greenbank Technology Park Blackburn BB1 5RR | 01254 504420 |
| Cadenza Communications Consulting UK Ltd | Cadenza Voice | 27 Old Gloucester St London WC1N 3XX | 07788 975996 |
| CAE Communications Ltd | CAE Communications Ltd | CAE House Colonial House Watford Herts WD24 4PT | 08708 500 510 |
| Calibre Network Ltd | |||
| Call Connect Ltd | Call Connect | PO Box 8026 Reading RG6 9DR | 0800 197 3545 |
| Call Flow Solutions Ltd | Call Flow Solutions Ltd | 1st Floor, Cornwallis House Pudding Lane Maidstone Kent ME14 1NY | 01622 686 449 |
| Call Options Bristol & Bath Ltd | |||
| Call Sense UK Ltd | Call Sense UK | Unit F19 Scope House Weston RD Crewe CW1 6DD | 08704 42 43 44 |
| Call Stream Ltd | Call Stream | Bordesley Hall The Holloway Alvechurch, Birmingham B48 7QA | 0870 787 7868 |
| Callagenix Ltd | |||
| Callmaster Ltd | Callmaster | Wrecclesham Road Wrecclesham Fernham, Surrey GU10 4PS | 01252 711 053 |
| Callmonitor Ltd | Callmonitor Ltd | 207 Regent Street London W1B 4ND | 0800 074 7456 |
| Calteq Ltd | Calteq Ltd | Weston Business Centre Parsonage Road Takeley Essex CM22 6PU | 0845 2000002 |
| Cambrian Communication Cyf | Cambrian Communications Cyf | 12 Hole in the Wall Street Caemarfon Gwynedd LL55 1RF | 01286 672866 |
| CANetworks Ltd | |||
| Capital Telecoms Ltd | Capital Telecoms | 2A Forest Drive Theydon Bois Epping Essex CM16 7EY | 07737 273535 |
| Capito Holdings Ltd | Capito | Caputhall Road Deans Livingston EH54 8AS | 0845 644 3601 - 01506 472 492 |
| Capstan Communications Ltd | Capstan Communications Ltd | Unit B, Blatchford Road Horsham West Sussex RH13 5QH | 01403 221728 |
| Captive8 Ltd | |||
| Care Telecom Ltd | Care Telecom | 53 Whitefriars Wharf Tonbridge Kent TN9 1QR | 01732 358 864 |
| Carter Allen | Carter Allen | 4b The Listed Building 350 the Highway LONDON E1W 4HU | 0870 053 7000 |
| Catalyst Communications Networks Ltd | Catalyst Communications Networks Ltd | 5 Cartwright House County Street London SE1 6AN | 020 7787 4100 |
| Caudwell Communications Ltd | Caudwell Communications | Christie Fields Derwent Avenue Manchester M21 7QS | 0161 451 1000 |
| Caudwell Communications Ltd | Caudwell Communications/Homecall | Christie Fields Derwent Avenue Manchester M21 7QS | 0161 451 1000 |
| Caudwell Communications Ltd | Homecall | Christie Fields Derwent Avenue Manchester M21 7QS | 0161 451 1000 |
| Cause Call | |||
| Cavendish Maintenance Ltd | |||
| CECOM | CECOM | 11 Pyle Road Bishopton Swansea SA3 3HH | 0800 019 8333 |
| Cedar Telecom Ltd | Cedar Telecom | Innovation House Mill Street Oxford OX2 0JX | 01865 458 609 |
| Celcom Ltd | Celcom Ltd | 277-279 Wood Street London E17 3ND | 0845 021 2323 |
| CellCall Ltd | |||
| Celltek Communications UK Ltd | Celltek | Globe House Moss Bridge Road Rochdale O46 5EB | 0870 905 0789 |
| Cellular Communications Ltd | |||
| Cencion Communications Ltd | Cencion Communications Ltd | 6 Brewery Yard Deva Centre Trinty Way Manchester M3 7BB | 0870 7515555 |
| Centrica Telecommunications | |||
| Centrix Ltd | Centrix Ltd | Winchfield Lodge Old Potbridge Road Winchfield, Hampshire RG27 8BT | 0870 143 4343 |
| Chalvington Communications Ltd | |||
| Chamber Communications Ltd | Chamber Communications Ltd | 40 Princess Street Manchester M1 6DE | 0845 6666551 |
| Change Implementations Ltd | Change Implementations Ltd | 5 Amhurst Road Telscombe Cliffs Brighton BN10 7AG | 0845 4506388 |
| Channel Force Ltd | Uscom Ltd | USC House Choseley Road Docking, Norfolk PE31 8LZ | 0870 750 8300 |
| Channel Media Communications | Channel Media Communications | 40 Hollerith Rise Bracknell Berkshire RG12 7GJ | 01344 670015 |
| Channel Networks Services Ltd | Channel Networks | Channel House 127 Duckmoor House BRISTOL BS3 2BJ | 0117 900 5000 |
| Charles Street Communications Ltd | Charles Street Communications Ltd | 6 Duke Street St Jame's London SW1Y 6BN | 020 7451 1313 |
| Charlton Networks Ltd | Charlton Telecom | The Canterbury Business Centre 18 Ashchurch Road Tewkesbury Gloucestershire GL20 8BT | 001684 856830 |
| Charterhouse Voice & Data PLC | Charterhouse Voice & Data PLC | Gate House 5 Chapel Place Rivington Street London EC2A 3DQ | 020 7613 7395 |
| Check Communications Ltd | |||
| Cheshire Cricket Telecom Ltd | Cricket Telecom | The Pavilion 26 Oakwood Way Hamble Hampshire SO31 4HH | 0845 450 3413 |
| Cheshire Telecom Ltd | Cheshire Telecom Ltd | Fernessia House 29 Avon Road Hale Altrincham, Cheshire WA15 0LB | 0870 034 5050 |
| Chess plc | |||
| Chester Communications | Chester Communications | 225 Hoole Lane Chester Cheshire CH2 3EP | 01244 348667 |
| Chime Telecom Ltd | |||
| Choice Numbers Ltd | Choice Non Geo & Choice Switch | Oakfield Wrotham Hill Road Wrotham Sevenoaks, Kent TN15 7PT | 020 7047 4446 |
| Choose Pure Solutions Ltd | Choose Pure Solutions Ltd | Imex Business Centre Brookfiled Road Arnold Nottingham NG5 7ER | 08700 116 383 |
| ChunkyChips.net Ltd | ChunkyChips.net Comms | ChunkyChips.net Ltd Units 1-2 Cornell Estate Navigation Road Chelmsford,Essex CM2 6HE | 0870 255 8000 |
| Churchill Office Solutions Ltd | Churchill Office Solutions Ltd | 381/385 Tyburn Road Erdington Birmingham B24 8HJ | 0121 6938208 |
| Citicom Network Services (UK) Ltd | |||
| Citiwide Facilities Management Ltd | Citiwide | 6 & 7 Harbour Exchange Square London E14 9GE | 0207 419 5992 |
| Citrus Networks UK Ltd | Citrus Networks VoIP Services | Orchard House 85 Mosslea Road Whyteleafe Surrey CR3 0DS | 020 7100 2410 |
| Citrus Telecommunications Ltd | |||
| City Numbers Ltd | City Numbers Ltd | Office 22 27 Colmore Row Birmingham B3 2EW | 0845 366655 |
| City Telecom | City Telecom | CET House 36 Golders Gardens London NW11 9BU | 0808 129 6000 |
| CityTel Management Ltd | CityTel Management Ltd | 17 Camp Road Rutherglen Glasgow G73 1TH | 0141 613 4445 |
| Claranet | Claranet | 21 Southampton Row London WC1B 5HA | 020 7685 8310 |
| Clarion Communication Management Ltd | Clarion Communication Management Ltd | Unit 5 107 Freston Road London W11 4BD | 08456 444 585 |
| Claritas Solutions Ltd | Claritas Telecommunications Ltd | Bowcliffe Hall Bramham Wetherby LS23 6LP | 01937 849966 |
| Clarity Telecom | Clarity Telecom | First Floor 103-113 Ravenhill Road Belfast BT6 8DR | 0800 912 0999 |
| Class Affinity Projects Ltd | Class Telecommunications | The White House Church Road Leatherhead, Surrey KT22 8BB | 0870 770 0321 |
| Clear Comms Ltd | Clear Comms Ltd | 26 York Street Westminster London W1U 6PZ | 0845 402 3002 |
| Clear Connect Ltd | Clear Connect | Connect House P.O. Box 143 Swansea SA2 0WT | 0870 990 9939 |
| Clear Telecom and Data Ltd | Clear Telecom and Data Ltd | 291 London Road Hadleigh Essex SS7 2BN | 01702 539896 |
| Clearcall 2000 Ltd | Clearcall 2000 | Unit 40 The Enterprise Centre Cranbourne Road Potters Bar, Hertfordshire EN6 3DQ | 0800 027 7066 |
| ClearPath IP Ltd | ClearPath IP Ltd | Innovate Office Lake View Drive Sherwood Park Nottingham NG15 0DA | 01623 687777 |
| Clearvoice Communications Ltd | |||
| Clickphone Ltd | Clickphone Ltd | Unit 9 17 Piries Place Horsham West Sussex RH12 1BF | 01403 339 809 |
| Club-Tel Ltd | Club Tel | Club House 2 Brookfield Avenue Blackrock, Dublin | 00 (353) 1278 9 |
| Club Call Management Ltd | Club Call Management Ltd | 69 North Lane Astley Tyldesley Manchester M29 7AB | 0845 056 5666 |
| Club Communications Ltd | |||
| Club Talk Ltd | Club Talk Ltd | Ailesbury Close Chippenham Wiltshire SN15 3TX | 08712 310 410 |
| CMR Consultants Ltd | |||
| CNS Ltd | Connectacom Network Solutions Ltd | Bradley House St Albans Lane Golders Green, London NW11 7QE | 020 8455 6044 |
| CNW Communications Ltd | |||
| Coach House Communications Ltd | Coach House Communications Ltd | The Coach House Sherridge Leigh Sinton Malvern Worcs WR13 5DB | 0870 4440888 |
| Cole Robert & Co Ltd | CRC Telecom | 35 Marsh Parade Newcastle ST5 1BT | 0870 787 0387 |
| Colloquium Ltd | Colloquium | 101 Abercorn Street Paisley PA3 4AT | 08454 330 000 |
| COLT Telecommunications | |||
| Columbus Telecom Ltd | Columbus Telecom | Milngavie Enterprise Centre Ellangowan Court Glasgow G62 8PH | 0870 060 3602 |
| Columbus Telecom Solutions Ltd | Columbus Telecom Solutions | 1 Colquhoun Drive Bearsden, Glasgow G61 4NQ | 0141 943 1943 |
| Comcen Computer Supplies Ltd | Comcen Technology | Bruce Road Swansea West Ind Park Swansea SA5 4HS | 01792 515 566 |
| Comm-Tech Martam Ltd | Comm-Tech Data Solutions | Communications Centre Rollesby Road Martham Great Yarmouth, Norfolk NR29 4RU | 01493 748274 |
| Commando Telecom Ltd | Commando Telecom | 724 Fulham road Fulham London SW6 5SF | 07952 717215 |
| Commexchange Ltd T/A Morden Networks | Modern Networks | Unit 2 Knowl Piece Wilbury Way Hitchin SG4 0TY | 01462 426 500 |
| Comms Direct Telecom Ltd | Comms Direct Telecom Ltd | Dominions House Dominions Arcade Queen Street Cardiff CF10 2AR | 0844 6331818 |
| Comms Factory Ltd | Comms Factory Ltd | Premium House The Esplanade Worthing West Sussex BN11 2BJ | 0870 990 5998 |
| Comms Factory Ltd | Lo-call Telecom Ltd | Premium House The Esplanade Worthing BN11 2BJ | 0845 450 0070 |
| Comms Factory Ltd | My Team | Premium House The Esplanade Worthing West Sussex BN11 2BJ | 0845-2410908 |
| Comms Factory Ltd | Your Team | Premium House The Esplanade Worthing West Sussex BN11 2BJ | 0845-2410908 |
| Comms Factory Ltd | YourCalls.Net | Premium House The Esplanade Worthing West Sussex BN11 2BJ | 08454 505 020 |
| Comms Management Ltd | Comms Management Ltd | Connaught House Riverside Business Park Benarth Road, Conwy North Wales LL32 8UB | 0845 450 3040 |
| Comms Uk Ltd | Comms Uk | Comms House Collingwood Road West Morrs, Wimborne Dorset BH21 6QW | 01202 894222 |
| Commsplus Ltd | Commsair | 51 Gazelle Road Weston-Super-Mare, North Somerset BS24 9ES | 01934 882 200 |
| CommsResources | CommsSolutions | Number One Sherman Roiad Bromley Kent BR1 3JH | 0208 313 6680 |
| Commsworld Ltd | Commsworld | Commsworld House Peffer Industrial Estate Peffer Place Edinburgh EH16 4BB | 0141 353 4211 |
| Commsworld Ltd | Commsworld | 100 Borron Street Port Dundas Business Park Glasgow G4 9XG | 0845 330 5033 |
| Communicate Better Business Solutions | Communicate Better Business Solutions | 222 Manchester Road Worsely Walkden Manchester M28 3LU | 0845 273 6666 |
| Communicate Business Solutions Ltd | Triangle Telecom | 6 Hill Road Clevedon North Somerset BS21 7NE | 01275 871122 |
| Communicate Information Ltd | |||
| Communication-Stem | Communication-Stem | 15-16 Lower Park Row Bristol BS1 5BN | 0845 2410000 |
| Communication-Tech UK Ltd | Commtech | Commerce House Bridgeman House Bolton Lancs BL2 1DW | 08707 106 688 |
| Communication-Tech UK Ltd | Communication-Tech UK Ltd | Commerce House Bridgeman House Bolton Lancs BL2 1DW | 08707 106 688 |
| Communication Networks Ltd | |||
| Communication Solutions Ltd | Communications Solutions Ltd | 1 Rhiw Road Colwyn Bay Conwy North Wales LL29 7TE | 0845 2700 672/3 |
| Communications Consultants Ltd | |||
| Communications EBS Ltd | Intelicoms | KBC House 42-50 Hersham Road Walton on Thames KT12 1RZ | 0870 2 40 30 20 |
| Communications Interactive Management Ltd | Communications Interactive Management Ltd | 12 Shenval House Harlow Essex CM20 2BD | 0845 127 9818 |
| Communications South Ltd | Communications South Network Services | 284 Hayling Avenue Portsmouth Hampshire PO3 6EF | 02392 833 993 |
| Communico UK Ltd | Communico UK Ltd | 15 Oakfield Street Pontarddulais Swansea SA4 8LN | 01792 885 352 |
| Communio Networks Ltd | Communio Networks | 1 Frogmore Road Hemel Hempstead Herts HP3 9TG | 0870 190 0870 |
| Company Communication UK Ltd | Company Communication UK LTD | 58 Buckinham Road Weston Industrial Estate West Super Mare North Somerset BS24 9BG | 0845 4021277 |
| Company Communications Ltd | Company Communications Ltd | Europa House Coppicemere Drive Crewe Business Park Crewe CW1 6GZ | 01270 503010 |
| Complete Business Solutions (NW) Ltd | Complete Business Solutions | 40 Devonshire Road Bolton BL1 4PQ | 01204-848414 |
| Complete Networks Ltd | Complete Networks Ltd | The New Media Center 36-42 New Tythe Street Long Eaton Nottingham NG10 2DB | 0845 070 4440 |
| Complete Systems | Complete Systems | Manor House Avenue Millbrook Southampton SO15 0LF | Unit 9 |
| Computacall | Computacall | Station House Midland Road Luton LU2 0HS | 01582 488885 |
| Computer Communications & Network Solutions Ltd | CCNS | Letchford House Headstone Lane Harrow Middx HA3 6PE | 0870 436 1821 |
| Computerease Ltd | Computerease Ltd | 4 Bramble Street Derby DE1 1HU | 0870 444 5414 |
| Computerised Business Systems Ltd | Computerised Business Systems Ltd | 554-556 Barton Road Stretford Manchester M32 9TD | 0161 755 9441 |
| Coms.Com Ltd | Coms.Net | 77 Queen Victoria Street London EC4V 4AY | 020 7148 3000 |
| Comtact Ltd | Comtact Ltd | 46-48 East Smithfield London E1W 1AW | 08452 757575 |
| Comtec Business Equipment Ltd | |||
| Comtec Telecom and Data Ltd | |||
| Comtxt Ltd | Comtxt | Cavell House Stannard Place St Crispins Road Norwich NR3 1YE | 01603 821 013 |
| Comxo TRIDrading Ltd | Comxo Trading Ltd | Pippin Grove 628 London Road Colnbrook Berkshire SL3 8QH | 01753 710 430 |
| Comxo TRIDrading Ltd | Perpetual Telecom Ltd | 3 Park Street Windsor Berkshire SL4 1LU | 01753 740 472 |
| Comxo TRIDrading Ltd | Swan Telecom | Pippin Grove 628London Road Colnbrook Berkshire SL3 8QH | 01753 710 430 |
| Concept 2000 Ltd | Concept 2000 Ltd | 72 New Bond Street Mayfair London W1S 1RR | 0870 199 3164 |
| Concept Coders Ltd | CC Telecoms | 105B The Big Peg 120 Vyse Street Hockley Birmingham B18 6NF | 0870 902 5580 |
| Concert Networks Ltd | |||
| Conduit Networks Ltd | Conduit Networks Ltd | 4th Floor 22 Buckingham Gate London SW1E 6LB | 020 7100 5522 |
| Connaught Communication Systems Ltd | Connaught Communication Systems Ltd | 14 Systems House Reddicap Trading Estate Sutton Coldfield, Birmingham B75 7BU | 0121 311 1010 |
| Connaught Telecommunications Ltd | |||
| Connect B2B Ltd | Connect B2B Ltd | Northfield House Northfield End Henley-on-Thames Oxfordshire RG9 2JG | 0800 881 8881 |
| Connect Communications Group Ltd | CC Networks Ltd | Hertford House 1 Cranwood Street London EC1V 9QP | 020 7950 3200 |
| Connect The World Ltd | Connect The World Ltd | Suite 12 Towerside 148 Wapping High Street Wapping London E1W 3PF | 0870 174 8575 |
| Connexions 4 London | Orbis Telecom | 22 St Peters Road Bournemouth Dorset BH1 2LE | 01202 299799 |
| Connexus Networks Ltd | Connexus Networks | Suite 2 Sperry House Bonds Mill Stonehouse Gloucestershire GL10 3RF | 0870 607 2121 |
| Consorte UK Ltd | Consorte UK Ltd | Pallinghurst Guildford Road Rudgwick West Sussex RH12 3BQ | 01403 824018 |
| Consortium (UK) Ltd | Consortium (UK) Ltd | Parkway Offices Moss Road Grimsby, North East Lincolnshire DN32 0LW | 0870 190 8900 |
| Consulting Networks Ltd | Consulting Networks Ltd | Customer Services Team 40 March Road Wimblington Cambridgeshire PE15 0RN | 0870 036 1234 |
| Consumer First Telecom Ltd | CF1 Telecom | PO Box 13 Portrush County Antrim BR56 8WZ | 0870 870 1125 |
| Contact Centre Communications Ltd | Contact Centre Communications Ltd | Bolney Place Cowfold Road Bolney, West Sussex RH17 5QT | 01444 880 301 |
| Contact Scotland Ltd | |||
| Continental Telecom Ltd | |||
| Continential Telecom | Continental Telecom | 2 The Close Richmond Surrey TW9 4QW | 0208 891 4791 |
| Converge-IT.net Ltd | Converge-IT | Barnett House 53 Fountain Street Manchester M2 2AN | 0870 770 0790 |
| Converged Communication Solutions Ltd | Converged Communication Solutions Ltd | 35 Huntly Street Aberdeen AB10 1TJ | 0800 8620 999 |
| Converged Technologies Ltd | Converged Technologies Ltd | 12 High Street Oliham Hampshire RG29 1LG | 01256 393010 |
| Converged Voice Solutions | Converged Voice Solutions Ltd | 20 Eden Way Winnersh Wokingham Berkshire RG41 5PQ | 0870 4050115 |
| Convergence (Group Solutions) Ltd | Convergence Group | 2 Lammas Centre Budbrooke Road Budbrooke Industrial Estate Warwick CV34 5WQ | 0845 270 2709 |
| Convergent Networks Ltd | |||
| Converse Telecom Ltd | Converse Telecom | Old Bank House 57 Church Street Staines Middx TW18 4XS | 0845 8739900 |
| Coralbridge Ltd | Coralbridge Ltd | 255/1 Silk House Park Green Macclesfield Cheshire SK11 7QJ | 01625 466 164 |
| Corinthian Technical Solutions Co Ltd | Corinthian Technical Solutions Co Ltd | Southern Counties House 27-43 Ifield Road Crawley West Sussex RH11 7AT | 01293 434224 |
| Corporate Business Telecoms | Corporate Business Telecoms | 31 Kings Exchange Tileyard Road London N7 9AH | 020 7503 3000 |
| Corporate Communications Europe Ltd | |||
| Corporate Management Telecom Ltd | Corporate Management Telecom (CMT) | 4 Oak Park Hunsdon Nr Ware Herts SG12 8QA | 08707 526 050 |
| Countrywide Farmers Energy | Countrywide Farmers Energy | Utilities Dept Defford Earls Croome Worcs WR8 9DF | 01386 757 333 |
| CPS Connections Ltd | CPS Connections Ltd | IC2 Keele University Science Park Keele Staffs ST5 5NH | 0870 787 9293 |
| CPS Telecom Ltd | CPS Telecom Ltd | 1st Floor 449-451 High Road Willesden, London NW10 2JJ | 0870 801 6060 |
| CPW Ltd | CPW | Technology House 9 Newton Place Charing Cross Glasgow G3 7PR | 08701 996 108 |
| Cranleigh Communications Ltd | ABS Technology Plc | Technology House Church Road Haslemere, Surrey GU27 1NU | 01428 664 900 |
| Creative Telecoms Ltd | Creative Telecoms Ltd | Studio 229 Great Gulidford Business Square 30 Great Guildford Street London SE1 0HS | 0871 222 7150 |
| Crimzon Communications Ltd | Crimzon Communications Ltd | Devonshire House Devonshire Lane Loughborough Leicestershire LE11 3DW | 01509 238233 |
| Crowthorne Associates Ltd | Crowthorne Associates Ltd | 8 Tavern Quay Rope Street London SE16 7TX | 0870 300 7000 |
| Crystaline Communications Ltd | Crystaline Communications | Boston House Business Centre 69-75 Boston Manor Road Brentford Middlesex TW8 9JJ | 0870 0666 016 |
| CT Networks Ltd | CT Networks Ltd | 3 The Maltings Wetmore Road Burton-on-Trent Staffordshire DE14 1SF | 01283 560 500 |
| CTI Telecom Ltd | CTI Telecom | 8 North Hills Brill Bucks HP18 9TH | 01844 239 750 |
| Custard IT Ltd | Custard IT Ltd | 3 Innovate Mews Lake View Drive Sherwood Park Nottingham NG15 0DA | 0870 401 9966 |
| CWL Associates | CWL Associates | 51 Granby Avenue Harpenden Herts AL5 5QP | 07977 236 785 |
| CWNETWORKS Ltd | |||
| Cygnet Telecom Ltd | Cygnet Telecom Ltd | Warwick House 41 Spring Road Hall Green Birmingham B11 3EA | 0870 787 4710 |
| dabs.com plc | |||
| Daisy Communications Ltd | Daisy Communications | Daisy House Suite 1 Lindred Road Business Park Nelson, Lancashire BB9 5SR | 0845 450 4520 |
| Dalecom | Dalecom | Unit 1C Toll Bar Workshops Station Road Sedbergh, Cumbria LA10 5HA | 01539 622 300 |
| Dataflow Communications Ltd | |||
| Datasharp Technology Systems Ltd | Datasharp Technology | 11 Anderson Crescent Elgin IV30 4HJ | 01343 810831 |
| Datasharp UK Ltd | Datasharp Network Services | Woodland Court Truro Business Park Truro, Cornwall TR4 9NH | 01872 266 666 |
| Datatech UK LTD | Datatech UK Ltd | Brodesley Hall Alvechurch Birmingham B48 7QA | 0845 0515151 |
| Datatel Networks Ltd | Datatel | 19 Peel Road Douglas Isle of Man IM1 4LS | 0870 333 4947 |
| Datavox | Datavox Solutions | Saddleworth Business Centre Huddersfield Road Delph OL3 5DF | 0800 0831173 |
| Davria Communications Ltd | Davria Communications | 60 Bartley Road Bensfleet, Essex SS7 4EL | 01268 799 312 |
| DCFM Telecom Ltd | DCFM | DCFM Telecom Ltd 1 Bridge Street Boston PE21 8QF | 01205 310644 |
| DCS Ltd | DCS Ltd | C/o 69 Lane Field Road Bideford Devon EX39 3RD | 07950 371041 |
| DCT Solutions | DCT Solutions | 167 High Street Strood ME2 4TH | 01634 226 580 |
| Decorum Connect | |||
| Deep Blue Networks | Deep Blue Telecom | Unit 3B Rudgate Court Walton Wetherby LS23 7BF | 0870 224 6200 |
| Definite Networks Ltd | Definite Networks Voice | Definite Networks Ltd The Nova Building, Herschel Street Slough Buckinghamshire SL1 1XS | 01753 701 807 |
| Delta - T Ltd | Delta - T Ltd | 3 Cook Close Brompton on Swale Richmond North Yorkshire DL10 7TY | 0800 0972324 |
| Denovo Communication Ltd | Denovo Communications | 33 Estelle Road LONDON NW3 2JX | 0207 424 9095 |
| Denovo Communication Ltd | Intelecom | 33 Estelle Road LONDON NW3 2JX | 0207 424 9095 |
| Design Communications Systems Ltd | |||
| Design Telecommunications UK Ltd | Design Telecommunications UK Ltd | 136 Central Road Worcester Park Surrey KT4 8HT | 0800 008 7351 / 020 8329 9610 |
| DETEWE Ltd | |||
| Devil7 Ltd | Devil7 | 90-92 Pentonville Road London N1 9HS | 0870 777 5767 |
| Dial Associates Ltd | Dial Associates Ltd | Millbrook High Bickington Umberliegh Devon EX37 9BX | 0845 458 6994 |
| Dial Business Systems Ltd | Icat Solutions | 17c St Helens Gardens London W10 6LW | 020 3084 3214 |
| Dialect Telecom Ltd | Dialect Telecom Ltd | Tithe Barn Blisworth Hill Farm Stoke Road Blisworth, Northants NN7 3DB | 01604 768770 |
| Difference Corporation Ltd | Difference communications | Merlin House Langstone Business Park Newport NP18 2HT | 0844 4931100 |
| Digicomm BCS Ltd | Digicomm BCS Ltd | 468 Halliwell Rd Bolton Lancashire BL1 8AN | 0870 444 6540 |
| Digital ip | |||
| Digitel Direct Ltd | Digitel Direct Ltd | Holmfeild Mills Holdsworth Road Halifax HX3 6SN | 08456 522 533 |
| Digitel Europe Ltd | Inet | Communications Centre 1 Ivy Street Priory Industrial Estate, Birkenhead Merseyside CH41 5EE | 0151 6500065 |
| Digitel Technology Ltd | Call-4-Less | 7 Cross Street Barnstaple, Devon EX31 1BA | 0870 750 0551 |
| Direct Communications International | DCI Telecom | Europa House Church Street Old Isleworth, Middlesex TW7 6DA | 0870 770 9901 |
| Direct Marketing Solutions Ltd | |||
| Direct Response Ltd | Direct Response Ltd | 9 Winchester House Kennington Business Park Cranmer Road London SW9 6EJ | 0870 414 9000 |
| Direct Telecom Ltd | Direct Telecom Ltd | 2D Belle Walk Moseley Birmingham West Midlands B13 9DF | 0121 552 6624 |
| Direct Telecommunications Systems Ltd | Direct Telecom | 16 Commercial Road Skelmanthorpe Huddersfield HD8 9DA | 01484 867 867 |
| Direct Telephone Services Ltd | |||
| Directory Business Services | Directory Business Services | Health Farm Wellingore Lincoln LN5 0DW | 01522 811 688 |
| Diva Telecom Ltd | Diva Telecom Ltd | 4100 Park Approach Thorpe Park Leeds LS15 8GB | 0844 873 23 53 |
| DM Business Solutions | Telstream | Patrick House 5 Maney Corner Sutton Coldfield West Midlands B72 1QL | 08707 525 354 |
| Dolphin Com Ltd | Dolphin Com Discounted Calls | P.O. Box 157 Nantwich, Cheshire LW5 7XD | 0800 195 2544 |
| Dolphin Communication Solutions Ltd | Dolphin Communications Solutions Ltd | 509 Katherine Road Forest Gate London E7 8DR | 020 8586 6000 |
| Dot Comm Consultancy Ltd | |||
| DRD Communications plc | DRD Communications plc | Connect House 21 Willow Lane Mitcham CR4 4NA | 020 8288 1234 |
| Drumbeat Communications Ltd | Drumbeat Communications Ltd | Rowan House Sheldon Business Park Chippenham Wiltshire SN14 0SQ | 01249 467400 |
| Du-Tel Ltd | |||
| du Pré plc | du Pré plc | Vo-Tec Centre Hambridge Lane Newbury Berkshire RG14 5TN | 01635 555 555 |
| DuoCall Communications Ltd | DuoCall Communications Ltd | Unit 6 Sycamore Centre Eastwood Trading Estate Rotherham S65 1EN | 08456 761000 |
| DV02 Telecom Ltd | DV02 Telecom Ltd | Unit 12 - The Admiral Park Airport Services Road Portsmouth PO3 5RQ | 0870 300 1055 |
| DX Tele-Solutions Ltd | DX Tele-Solutions | 4 Tansley View Wolverhampton WV2 1HT | 0870 896 4380 |
| DX Tele-Solutions Ltd | Talk Warehouse | 4 Tansley View Wolverhampton WV2 1HT | 0870 896 4380 |
| DX Telecom Ltd | DX Telecom Ltd | DX House P.O. Box 143 Swansea SA2 0WT | 0870 990 8008 |
| DXI Networks Ltd | DXI Networks | Service Management Centre DXI Networks Limited 24 Chiswell Street London EC1Y 4TY | 020 7579 8299 |
| Dynamics Computer Consultants Ltd | Dynamics | 5e Longrock Industrial Estate Penzance Cornwall TR20 8HX | 01736-888123 |
| e-Shop UK Ltd | |||
| E-Tel Systems | E-Tel Systems | 1 Cwrt Pencoedtre Barry South Glamorgan CF62 9BS | 01446 741530 |
| E7even UK Ltd | Touch Telecom | Suite C9 Powerhub Business Centre St. Peters Street Maidstone ME16 0ST | 0870 224 5122 |
| Easi-Call UK Ltd | |||
| Easi-tel Ltd | Easi-tel Ltd | 15 Riverside Studios Amethyst Road Newcastle Business Park Newcastle-Upon Tyne NE4 7YL | 0870 789 7788 |
| East Point Telecom Ltd | East Point Telecom | 15 Waveney Road Lowestoft Suffolk NR32 1SP | 01502 532732 |
| Easy-Dial Ltd | Easy-Dial | P.O. Box 8213 Chiswick, London W4 3WR | 0870 120 2033 |
| Easy Networks Ltd | Easy Networks Ltd | Unit 1.1 Central Point Kirpal Road Portsmouth PO3 6FH | 023 9277 8800 |
| Easynet Group Plc | Picnic | Picnic PO Box 57952 London W4 5PD | 08702 222222 |
| Easynet Group Plc | Skytalk | Head of Voice and Switch Development Easynet Ltd 1 Brick Lane LONDON E1 6PU | 020 7900 1226 |
| Easytone Telecom (UK) Ltd | Easytone Telecom (UK) Ltd | 1st Floor 12-13 Little Newport Street London WC2H 7JJ | 0207 437 7123 |
| Ecam Solutions Ltd | Ecam Solutions Ltd | 289/293 Ballards Lane London N12 8NP | 0870 080 2333 |
| Echo Network Services | Echo Communications | Echo House 27-33 Burr Road London SW18 4SQ | 020 8870 4000 |
| Eclipse Networking Ltd | Eclipse Internet | Portland House Longbrook Street Exeter Devon EX4 6AB | 0845 122 4333 |
| Eclipse Telecom Networks Ltd | |||
| Ecocall Ltd | Ecocall Ltd | Ver House 23-25 High Street Redbourn, Hertfordshire AL3 7LE | 01582 793 007 |
| Ecomtel Ltd | Ecomtel | PO Box 5289 London SW11 3US | 020 7108 1678 |
| Economy Calls | Economy Calls | Churchill House Churchill Way Cardiff CF10 2HH | 0845 234 0200 |
| Ecosse Group Ltd | Openline Communications | Unit 7G Anniesland Ind. Estate Netherland Road Glasgow G13 1EU | 0141 950 2640 |
| Ecosse Telecommunications Ltd | |||
| ECS Telecommunications Ltd | Umer | 258 Hackney Road London E2 7SJ | 0870 145 8300 |
| ED Communications Ltd | ED Communications Ltd | Enterprise House Henfield Road Small Dole West Sussex BN5 9XH | 0870 010 7710 |
| Eden Business Support Ltd | Eden Business Support | Gibbs House Kennel Ride Ascot Berkshire SL5 7NT | 0870 224 0445 |
| Eden Communications | Eden Communications | 25 High Street Edenbridge Kent TN8 5AB | 01732 865 313 |
| Edge Solutions Ltd | |||
| Edirect Computers Ltd | |||
| Effective Communication Solutions Ltd | ECS Telecoms | 5 Gladstone Road Liverpool L19 1RR | 08450 515 030 |
| EFL Telecom Ltd | EFL Telecom | 5 Thursday Street Haydon End Swindon Wiltshire SN25 1RG | 0844 418 0188 |
| Eiretel | |||
| Eker International Ltd | Eker Telecom | Davina House 137-149 Goswell Road London EC1V 7ET | 0845 108 0557 |
| Elite Business Systems UK Ltd | Elite Business Systems UK Ltd | 26-27 Chartergate Quarry Park Close Moulton Park Northampton NN3 6QB | 0870 899 3355 |
| Elite Calls (UK) Ltd | Elite Calls | The Lockhouse Frogmore Road Aspley, Hemel Hempstead Herts HP3 9RW | 0870 0665651 |
| Elite Telecoms (Dorset) Ltd | Elite Telecoms (Dorset) Ltd | Suite 2, Cleveland Court Cleveland Road Bournemouth Dorset BH1 4QB | 01202 392 970 |
| Elitetele.com plc | Elitetele.com | Rainford Hall Crank Road Crank St Helens, Merseyside WA11 7RP | 0870 990 8000 |
| Elphinstone Communications Ltd | Elphinstone Communications | 295 Fenwick Road Giffnock, Glasgow G46 6UH | 0141 620 3000 |
| Emedia Telecom | Emedia Telecom | 32 Grove Place Bedford MK40 3JJ | 0845 226 0260 |
| Empha Tech Ltd | |||
| Emtel Ltd | Emtel | Mercury House Shipstones Business Centre Northgate Nottingham NG7 7FN | 0845 450 4556 |
| Enable Communications Ltd | Enable Communications | 27 Waters Edge Canterbury Kent CT1 1WX | 05602 963598 |
| Energy Telecom Ltd | Energy Telecom | Freepost Energy Telecom PO Box 6918 Derby DE1 9EL | 0870 755 6699 |
| Enron Direct Ltd | |||
| Entacall Telecommunications Ltd | Entacall Telecommunications | Stafford Park 6 Telford Shropshire TF3 3AT | 08707 709 394 |
| Entanet International Ltd | Entacall Telecommunications | Stafford Park 6 Telford, Shropshire TF3 3AT | 0870 770 9656 |
| Enterprise Carrier Services Ltd | |||
| Entigy Ltd | Quik Talk | Imperial Chamber Prince Albert Street Crewe Cheshire CW1 2DX | 01270 212199 |
| Entrepreneur.com | |||
| Equate Business Solutions Ltd | EQ8 Telecom | Suite 13 Pontsychan House Abersychan Industiral Estate Abersychan, Pontypool NP4 7BA | 0845 085 0052 |
| Equate Group Plc | Equate Group Ltd | 3 Watermill Way Weston Turville Bucks HP22 5SR | 01296 612 427 |
| Equip-IP Ltd | equ-IP | Albany House 14 Shute End Wokingham Berkshire RG40 1BJ | 0118 3231674 |
| Equip Communications Ltd | Equip Communications Ltd | Unit 8F Alder Road West Chirton (North) Ind Est NE29 8SD | 0191 270 8000 |
| Equitalk.co.uk Ltd | Equitalk | Innovation Centre Heyford Park Upper Heyford Oxon OX25 5HD | 0800 161 3837 |
| Essanet Ltd | BBTALK | 8 Cromwell Business Centre Howard Way Newport Pagnell Milton Keynes MK16 9QS | 01908 888327 |
| Esscom Communications Ltd | Esscom Communications Ltd | Century House Westcott Venture Park Westcott Bucks HP18 0XB | 08704 232 320 |
| Essensys Ltd | Essensys Ltd | 16th Floor Centre Point 103 New Oxford Street London WC1A 1DD | 020 3102 5252 |
| Ethcom Ltd | |||
| Ethernet Communications | Ethernet Communications | Unit 9, Limefield House Limefield Brow Bury BL9 6QS | 0161 7633131 |
| Ethos Voice & Data - EVAD | EVAD | 124-128 City Road London EC1V 2NJ | 020 7253 4482 |
| ETS Communications Ltd | ETS Communications Ltd | Wakefield Road Horbury Wakefield West Yorkshire WF4 5HQ | 01924 237000 |
| Euphony Communications Ltd | Euphony | Belvedere House Basing View Basingstoke RG21 4HG | 01256 857 100 |
| EurISP | EurISP Ltd | 6 Queensgate Huddersfield HD1 2RD | 0871 2202233 |
| Eurolink Telecom Ltd | Eurolink Telecom | Swan House Bonds Mill Estate Stonehouse Glos GL10 3RF | 08450 755 500 |
| Europa Network (UK) Ltd | Europa Networks | Warwick House 41 Spring Road Hall Green Birmingham B11 3EA | 0870 756 0646 |
| Europa.net Ltd | Europacom.net | The Rectory Stoneham Park Eastleigh S050 9NW | 023080 646 305 |
| European Communications | European Communications | Communications House 17 Chesham Avenue Flixton Manchester M41 8SS | 08709 500 074 |
| European Telecom Solutions | European Telecom Solutions | PO Box 104 Neath SA11 2WZ | 01639 814 800 |
| European Utility Management | European Utility Management | Liberty House 222 Regents Street London W1B 5TR | 0207 0601900 |
| Eurotel Communications Ltd | Eurotel Communications | HB House Foleshill Enterprise Park Courtaulds Way Coventry CV6 5NX | 0870 750 9999 |
| Eurotel Ltd | Eurotel Ltd | Empire House Mulcture Hall Road Halifax HX1 1SP | 01422 864 097 |
| Everlast Systems Ltd | Everlast Systems Ltd | 81 High Street Salisbury House Potters Bar EN9 5AS | 0845 2000512 |
| Evolution Voice and Data PLC | Evolution Global Networks | 36 Great St. Helens London EC3A 6AP | 020 7628 2800 |
| Evolve Telecom Ltd | Evolve Telecom | Suite 1-2 Chalkwell Lawns 648-656 London Road Westcliff on Sea Essex SS0 9HR | 0870 333 3734 |
| Excel Communications (UK) Ltd | |||
| Excel Telecom Ltd | |||
| Excel Telecommunications Network Ltd | Excel Telecommunications Network Ltd | Greenlands Business Centre Studley Road Redditch B98 0NZ | 01527 527 747 |
| Excell Network Solutions Ltd | |||
| Exchange Communications Ltd | Exchange Communications Ltd | Exchange House Kerr Street Kirkintilloch Glasgow G66 1LS | 01417 768 581 |
| Exchange UK | |||
| Executel Ltd | Executel | West Wing Cameron House Metro Centre Gateshead NE11 9XW | 0191 493 1111 |
| Expanse (UK) Communications Ltd | ECL Telecom | The Old Rectory Church Road Sevington, Ashford Kent TN24 0LD | 0870 242 1718 |
| Eze-Talk | |||
| F H Brown Office Technologies Ltd | |||
| Facilities Management | FMUK | Saddleworth Business Centre Huddersfield Road Delph OL3 5DF | 01457 820022 |
| Fastnet International Ltd | Fastnet International | Shaftsbury Court 95 Ditchling Road Brighton East Sussex BN1 4ST | 01273 662 888 |
| Fax Information Services Ltd | Telfis | 7th Floor, Times House Throwley Way Sutton Surrey SM1 4AF | 0208 652 1100 |
| Fax2Mail Ltd | Fax2Mail | Venture West New Greenham Park Newbury Berks RG16 6HN | 0870 114 1140 |
| FCP Communications | FCP Communications | 19-20 Bourne Court Southend Road Woodford Green Essex IG8 8HD | 01279 60 32 91 |
| Fenix Networks Ltd | Fenix Networks Ltd | Unit 3 Montgomery Business Park 38 Montgomery Road Belfast BT6 9HL | 028 90400400 |
| FHTM Ltd | FHTM Ltd | United Business Centres Plc Midsummer Court 314 Midsummer Boulevard Central Milton Keynes MK9 2UB | 0870 141 9619 |
| Fineline Communications Ltd | Tempest Telecom | Third Melrose Roxburghshire TD6 9DR | 08700 505 015 |
| Fintech Consultants Ltd | Fintech Communications | 5 St John's Lane London EC1M 4BH | 020 7549 1654 |
| Fire Telecom Ltd | |||
| First Active Communications Ltd | |||
| First Call Communications Ltd | i Communications | 3-4 Byron Place Clifton Bristol BS8 1JT | 0117 952 9189 |
| First Choice Mobiles Ltd | First Choice Mobiles First | Southern Gateway Speke Boulevard Liverpool | 01514 865 222 |
| First European Telecom Ltd | First European Telecom Ltd | Ramsay Court 111 Ecclesall Road South Sheffield S11 9PH | 0800 195 9200 |
| First Global Telecom Ltd | First Global Telecom Ltd | Tottenham Green Enterprise Centre Town Hall Approach London N15 4RX | 0870 224 1120 |
| First Group Dynamics Ltd | First Group Dynamics Ltd | Palehouse Barn, Palehouse Common Framfield Uckfield East Sussex TN22 5QY | 01825 890 099 |
| First National Telecom Services Ltd | gotalk | 3rd Floor The Argyle Centre York Street Ramsgate CT11 9DS | 0800 097 7777 |
| First Voice Group Ltd | |||
| First4Telecoms Ltd | |||
| Fizz Telecom Ltd | Fizz Telecom Ltd | CBS House, The Courtyard Alban Park Hatfield Road St Albans, Hertfordshire AL4 0LA | 0845 672 7272 |
| Flat Rate Telecom | Flat Rate Telecom | 46 Clerkenwell Close London ECR1 0AT | 0845 223 7500 |
| FLR Spectron Ltd | FLR Spectron | 4th Floor, Berwick House 8-10 Knoll Rise Orpington Kent BR6 0EL | 0870 997 0000 |
| Fluid Network Solutions Ltd | |||