Verizon Wireless said it is disconnecting a small group of customers who use vast amounts of data in rural areas where Verizon relies on roaming agreements with smaller network operators.

"Earlier this month we notified a small group of customers who are out of contract and primarily use mobile data on other wireless companies’ networks that we won’t be their service provider after July 30, 2017," a Verizon spokesperson told Ars today. "This only affects a few people who primarily roam on other networks and does not affect customers who primarily use Verizon's own network."

The customers who are affected "are using vast amounts of data—some as much as a terabyte or more a month—outside of our network footprint," the company said. Verizon gave the customers several weeks' notice so they have time to port their numbers to new providers. Verizon provided no option to switch to different plans.

"We regularly review accounts with data use that primarily takes place outside of the Verizon network," Verizon also said.

Verizon pays for roaming on rural carriers

The change affects a mix of customers on limited and unlimited data plans. The common thread is that these customers are supported by Verizon’s LTE in Rural America (LRA) program, which relies on a partnership between Verizon and small rural carriers who lease Verizon spectrum in order to build their own networks. Verizon may be losing money on customers using unusually large amounts of data because Verizon pays the rural networks for roaming.

BGR reported the change yesterday, noting that Verizon customers can roam on the rural networks without paying extra.

"From a customer perspective, there’s no visible difference between being on Verizon’s network or [an LRA] partner," BGR wrote. "You’ll still get an LTE signal in most areas, and in theory, you’re meant to be able to use your regular Verizon plan with no limitations on any partner carrier."

BGR also pointed to a user forum with comments from people who received the notification.

"Verizon has no way to throttle back users in these areas so users are taking full advantage of that," one person wrote. "Several people have been using LTE as home broadband. I tethered 12+ GB in a single day with no throttle."

On its own network, Verizon started offering new unlimited data plans in February, but it reserves the right to throttle speeds after a user passes 22GB in a month. The throttling is applied only when the customers connect to congested cell towers.

At the same time, Verizon has occasionally tried to shed some customers on older unlimited plans that aren't offered anymore. In January, Verizon Wireless said that customers with grandfathered unlimited data plans who use more than 200GB a month would have to switch to limited plans or be disconnected.