• 40 Bowling Green Lane, London, England, EC1R 0NE
  • info@number-testing.co.uk
  • 03300 106600

Landline and Mobile Telephone Number Testing and Validation Service

Are your call centre agents wasting time and money listening to unobtainable tones? We are a telecommunications engineering company that provides a landline and mobile telephone number verification service. Our simple upload verification service allows our clients to easily validate and verify their telephone number data.


Designed by our associated telecoms engineering firm Cityfringe, our carrier-grade telecoms platform passively tests Telcoms networks and exchange equipment to rapidly detect the condition of thousands of telephone lines (numbers) per hour, without denying dial tone to subscribers at any stage during testing. Our service is fully compliant with Ofcom rules and regulations and adheres to all relevant DMA guidelines.

If you have telecoms or IT related problems to solve, then please

Visit the Cityfringe Website

Bulk testing can identify the following:
  • *
    Number in service (normal working order)
  • *
    Line dead/ out of order/no such number/number not recognised/not assigned
  • *
    Anonymous calls rejected/number not accepting incoming calls
  • *
    “number changed” announcements

Do you need to remove dead phone numbers from your lists?

Our carrier grade system can passively check the condition of thousands* of telephone numbers per hour and produce reports which can include details on the following line conditions:
  • Number in service (normal working order)
  • Line out of order/no such number/number not allocated etc
  • Anonymous calls rejected/number not accepting incoming calls
  • It even identifies lines with a “Changed Number Intercept” message on them !

*Our system can currently test around 30,000 numbers per hour

Our Team

We specialise in solving complex technical problems for telecoms operators and corporate customers.

Our associated engineering company City Fringe, offers a range of technology solutions that are carefully designed to empower technology dependent organisations.

It was through this work that we originally devised our phone number testing and validation solution.

Peter Muswell CEO

Developed the platform and is responsible for driving the business forward.

Julian Dilley Marketing Consultant

Responsible for opening doors

Portia Harrington Project Manager

Responsible for managing client relations and managing complex projects.

Guy Muswell Sales & Business Development

Responsible for client relationships and turning leads into positive outcomes.

Contact Us

To request a free trial please call 03300 106600
or email:- info@number-testing.co.uk