Telus says it will start shutting down Public Mobile's cellphone network in May, moving the more than 260,000 discount customers to its main network over a period of several months.
Telus, which bought Public Mobile last fall, says it is making the switch because the small carrier's network uses old technology.
The Vancouver-based telecom says Public Mobile's network will be upgraded and become part of its faster, main network, although customers will have to upgrade their older talk-and-text phones.
The move should be completed by mid-August or so, and Telus says it will give Public Mobile customers at least one month of free service and discounts on smartphones.
Telus also says it will keep Public Mobile's $19 monthly talk-and-text plan until the end of this year.
The Vancouver carrier had said last fall that it would move the Public Mobile customers to its main network, but didn't give a specific timeline until Thursday.
"This move from a small, outdated network to our modern national network is needed to ensure the brand is economically viable," said Kevin Banderk, chief Koodo officer at Telus and general manager of Public Mobile.
Telus received approval from Industry Canada last October to buy Public Mobile. At the time, Industry Canada said transaction didn't affect competition in the wireless industry. Public Mobile had purchased spectrum — radiowaves needed to operate cellphone networks — that wasn't considered technologically valuable.
Public Mobile bought its spectrum in 2008 and was never under any restrictions that would have prevented it from being sold.
Startups Wind Mobile and Mobilicity bought a different kind of spectrum that the government does not appear to want sold to Rogers, Bell or Telus.
All three startups launched in recent years have made only a dent in attracting consumers away from the big three carriers, who have about 27 million customers among them.
Telus has twice tried to buy struggling Mobilicity, but both times the deal was rejected by Industry Canada.
Both Mobilicity, under creditor protection, and Wind Mobile are still seeking buyers.