Dialing instructions for new UW Centrex VoIP system

For years, UW and State Centrex phone users have been able to contact each other by simply dialing a five-digit version of their phone numbers. This dialing process will gradually stop working as campus transitions to VoIP (Voice over Internet Protocol). In preparation for the transition, we encourage all Centrex users to begin dialing:

  • 9 + the seven-digit phone number for calls within your area code
  • 9 + 1 + area code + seven-digit phone number for calls outside your area code

If you dial a five-digit extension from a Centrex line and don’t get through, please redial using the 9 + the seven-digit phone number.

This change is part of the service conversion from Centrex analog to Cisco VoIP service, affecting about 20,000 UW–Madison phone users. It does not affect those who are already using the Cisco VoIP service. Cisco users should continue to use the dialing sequences provided when they received their training.

DoIT is informing all department phone service liaisons, as well as all Centrex users of the change. UW Health, UW–Extension, UW Colleges and UW System Administration are informing their employees of similar changes.

If you have any questions or concerns, please see the KnowledgeBase article: Centrex – Dialing Instructions, or contact the DoIT Help Desk at 608-264-HELP.