Not all phone numbers are portable. Generally speaking, phone numbers are portable if they belong to a busy phone exchange in a larger population center - a city. Small towns generally do not have portable numbers due to the economics of providing expensive PORTS per neighbourhood exchange. A phone company will not invest in a PORT if it cannot get at least 200 paying VoIP subscribers per month.
An example of this is Kelowna, British Columbia. Even though it has a fairly large population it also has 5 phone exchanges within its service area but VoIP lines are only provided to the main Kelowna Exchange so only phone numbers in that exchange can be ported over to the VoIP service. This option is not available for the Mission, Rutland, Lakeview Heights or Westbank exchanges. You can get a VoIP phone number from the Kelowna Exchange even if you are living in the other areas but you cannot port your number from those other areas to a VoIP service - you would have to change your phone number if you wanted to use our VoIP service.
