Verizon

It's getting tougher to be an unlimited data customer on Verizon Wireless.

The New York telecommunications giant said Thursday that subscribers on grandfathered unlimited-data plans -- the company stopped offering them to new customers in 2011 -- would face a $20 increase in their monthly bill. Customers will see the first increase in their bill after November 15, although a small minority of unlimited users still on contract won't see the hike until it expires.

It's the latest wrinkle thrown at unlimited data customers as Verizon attempts to move them to tiered plans with limits on how many movies, videos and songs they can download to their smartphones. The move also underscores the rising cost of delivering more data to consumers, with Sprint last week raising its unlimited rate by $10 a month.

Verizon's increase will push up the monthly cost of unlimited data from $30 to $50. With voice calling and texting added in, a customer's monthly bill could easily top $100.

The number of Verizon customers on an unlimited plan is relatively small; the company said they account for less than 1 percent of its base. But they have stubbornly hung on despite losing access to subsidized smartphones and other perks granted to fellow customers. Verizon also offers unlimited data to business and government customers, but they won't see the rate hike.

Like Verizon, AT&T long ago stopped offering unlimited data, although neither has forced anyone off their plans. Smaller rivals T-Mobile and Sprint still offer the option.

Verizon, the nation's largest wireless carrier, last year attempted to set a policy that would allow it to throttle, or slow down, data speeds for heavy users of unlimited data. It backtracked on the plan last fall after its customers and the Federal Communications Commission voiced their objections.

A Verizon spokesman noted that some customers could actually end up saving money by switching to a tiered plan, and that not all unlimited data users stream enough movies and songs to justify the expense.

"There are options out there that don't involve unlimited that may be a better fit for you," he said, declining to break out how much data an unlimited customer typically uses.

Verizon said it would work with customers once the rate increase takes effect to see if it makes more sense to switch plans.

In a minor concession to its unlimited customers, Verizon said it would allow them to participate in the monthly installment plans for new devices. Customers previously had to pay the full price of a new smartphone upfront.