According to new research by the Harris Poll, commissioned by Consumer Cellular, an estimated 73 million people have accepted these offers without realizing the financial commitment involved.
Ed Evans, CEO of Consumer Cellular, said while the phones may be advertised as free, consumers are actually paying for them through their rate plans.
"Most of the carriers require you to actually sign up for their most expensive, unlimited plan and in fact, consumers aren't using that much data," he said.
Evans advises consumers, especially those over 50, to check their actual data usage before committing to a plan.
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If you need phone financing, that's ok," he added. "There's plenty of interest-free phone financing that's out there, but then go shop for a rate plan that is really going to work for you and what your data patterns are."
Evans also warns that unlimited data plans often come with fine print. While they may promise high-speed data, there's usually a cap, and once that limit is reached, speeds can be significantly reduced.