AT&T and CenturyLink plan to join Verizon in banning vague third-party charges on land-line phone bills, after U.S. Sen. Amy Klobuchar sent letters to the telecommunications companies, urging them to stop the practice.


Companies use the tactic, commonly known as cramming, to litter phone bills with vague charges that, unbeknownst to many customers, boosts the cost of monthly service.


After Verizon agreed to stop cramming last month, Klobuchar sought out the other companies in her continuing campaign to crack down on the practice, which led to $10 billion in sometimes unauthorized fees on landline phone bills over a five-year period, a study by the Senate Commerce Science and Transportation Committee found.


"While this is welcome news, it's important that we continue to crack down on deceptive billing practices so we don't see the same cramming tactics land on consumer's cell phone bills," Klobuchar said in a statement.


As a member of the Senate Commerce Subcommittee on Communications, Technology and the Internet, Klobuchar has also pressed Federal Communications Commission officials to crack down on cramming.