Bruce Cran, president of the Consumers' Association of Canada, said it's a national problem that affects every cellphone provider in the country.
"You've got to be very vigilant with your bill," said Cran, who added that he has received complaints from people who have been dealing with the problem for almost a decade.
"We get complaints from the Pacific to the Atlantic on this issue."
A Saskatchewan woman says her mobile Internet hot-spot device, called a Mi-Fi, has incurred international roaming charges, even though it hasn't left her property near Alameda, a community not far from the U.S. border with North Dakota.
Kimberley Dietze told radio station CJME that she received an automatic voice message from SaskTel saying she had surpassed her $100 data-roaming limit.
"It happens anywhere along the border, or can happen, where the population is low, and the type of equipment maybe is a little old or else is inadequate in some other fashion," Cran said.
He added that he has dealt with the problem personally at his home in Delta, B.C., which is south of Vancouver about a kilometre from the U.S. border.
In the past, he would call Rogers Communications every month to address roaming charges, Cran said, but now it happens about two or three times a year.
He is often alerted to the problem with a "Welcome to the United States" text message while he's sitting in his living room.
"The big source of annoyance is that you have to deal with this on an ongoing basis.
Cran's organization has been trying to draw attention to the problem.
"I do think that (cellphone providers) have an obligation to put something in play that takes care of this for their clientele."
SaskTel spokeswoman Darcee MacFarlane said it's a long-standing issue in rural communities near the Saskatchewan border.
"There's actually, to be perfectly frank, very little that we can do," she said.
Weather, terrain, location and even the type of device being used can affect cellphone and data reception, she said. "It's the nature of the wireless technology."
Cellular towers typically have a radius of up to 30 kilometres, so U.S. towers near the border can cause interference, MacFarlane explained.
Customers are made aware of the problem when they buy cellphone plans, she added.
Dietze told CJME that SaskTel agreed to waive the charges on a one-time basis.
"We typically do not refund on this situation due to the fact that we try to give an up-front notice that it is something that can occur," MacFarlane said.
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