Telephone Number Portability

Taking Your Number With You 

Number portability is the ability to keep your same telephone number when you change providers. 

For example, if you had the phone number (555) 434-2457 with your AT&T landline, you can change to Charter and keep the (555) 434-2457 number. Note that this only works if you change providers – not locations. 

If you intend to port your number, do not disconnect service from your prior provider until your new provider has service running and has successfully ported your number. If you surrender service before the number can be ported, the number will be removed from service, and it may not be possible to get the number back.

If You Experience Problems when “Porting” Numbers 

Generally, number portability occurs seamlessly and invisibly when you change telecommunications providers. However, the process does require your old and new providers to make a number of simultaneous network changes to keep your calls flowing, and in very rare occasions this can go awry. Contact your new providers first​, but if that is not effective, please contact the Commission. The Commission has experience mediating these issues. 

Porting Numbers in Rural Areas 

Customers living in rural areas may experience problems porting numbers to some providers. For technical reasons, to make a number port function, the new provider must establish connecting facilities linking to the original provider. Some providers are unwilling to invest in such facilities in rural areas, which means they cannot accept ported numbers in those areas. 

Geographic Number Portability 

To date, the network does not have the ability to port landline numbers outside the geographic area to which they were originally assigned. This is because telephone numbers are, in effect, maps, with the first three numbers (the area code) defining a portion of a specific state, and the next three numbers (called the NNX) defining a neighborhood. Breaking that geographical linkage is technically feasible, but would impose considerable costs on both providers and customers. Both the Commission and federal authorities are working on evolving the network to make geographic number portability possible, but that capability is still several years off. 

For More Information

If you have questions or problems involving number portability, please contact Peter Jahn at (608) 267-2338, or via email at peter.jahn@wisconsin.gov.​