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ISDN

ISDN is a business-only digital Voice Service which improves the clarity and quality of calls. We have two variants of ISDN - ISDN2 (2 channels) & ISDN30 (between 8 & 30 channels) both of which provide crystal clear telephony, which means you have the capability to make or receive 2, or between 8 and 30 concurrent calls.

ISDN runs on a standard 12 month contract, with competitive call rates, no small print and no minimum spend, unlike some of our competitors.

Call our Sales team on 0845 058 9000

Our ISDN services

Our ISDN services are offered on a 12 month contract, and we do not charge any call connection fees, or insist on any minimum call spend; you simply benefit from our competitive call rates.  

It is free to transfer your existing service to us, and you can benefit from the low channel rental and low call costs 10 working days from your order being confirmed. During the transfer process there is no downtime, and no change to the physical aspects of your service.  You are able to make and receive calls as normal, and there will be no changes to your phone numbers.

Our excellent Customer Service and Technical Support comes as standard.  You can also choose the Premium Care option for 24/7/365 cover, to give you peace of mind that your service is in safe hands.

Features and benefits of our ISDN services

  • High quality digital voice service for businesses of all sizes
  • No call connection fees or minimum call charges on any phone line or mobile line. All calls billed per second, and there is no minimum call spend
  • Free transfers, with no service disruption or downtime and no need to change any of your phone numbers
  • 12 month contract
  • Award-winning Customer Service and Technical Support, with an option for 24/7/365 Support available
  • Direct Dial In Numbering, so all staff and departments can be contacted directly
  • Always on connections, providing fast and secure communications.
  • Paperless billing as standard. All your calls are shown on the Customer Portal, and you are able to access these 24/7

What you will need to use our ISDN services

  • A PBX that is compatible with ETSI (European Telecommunications Standards Institute) signalling

ISDN pricing

Product Options Set Up Fee Monthly Rental
Transfer fee FREE -
ISDN30 Rental per channel - £14.70
ISDN2 Rental per circuit (2 channels) - £27.00
Rental charge per DDI number - £0.30



ISDN30 Connection charge (New installations only) £680.00 -
ISDN2 Connection charge per circuit (2 channels) £180.00  
ISDN 30 Installation charge per channel £40.00 -
Installation charge per DDI installation £90.00 -
DDI connection charge per number  £0.90 -

ISDN call rates (pence per minute)

Destination Daytime
(7am - 7pm) 		Evening
(7pm - 7am) 		Weekend
(Fri 7pm - Mon 7am)
UK Landline 1.00p 0.85p 0.85p
T-Mobile 9.00p 8.51p 7.23p
O2 9.00p 7.23p 7.23p
Orange 9.00p 7.23p 7.23p
Vodafone 9.00p 7.23p 7.23p
3 10.00p 7.23p 7.23p
       
0845 4.68p 1.70p 1.70p
0870 3.40p 1.28p   1.28p

ISDN Support options

Support Options Description Monthly Rental
Standard We aim to resolve the fault by the end of the next Working Day, when raised to Zen before midday, during Business Hours of 0900-1700 Mon to Fri FREE
Premium We aim to resolve the fault within 8 Hours, 24/7/365 £5.00 per channel

ISDN calling features

Calling Features Description Set Up Fee Monthly Rental
Administration Provided Call Forward of Voice & Data Calls All calls to the service are diverted to a Single Destination - £2.00
Calling Line Identity Presents or Restricts the number of the line on Outbound Calls - £0.50
Connected Line Identity Shows the number where the call is connected, which may be different from the number dialled - £0.50
Presentation Number Present a generic number on all outbound calls £60.00 £0.50

Call our Sales team on 0845 058 9000

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