There are 300 million third-party charges totaling $2 billion on U.S. phone bills each year, according to the Senate Commerce Committee.
What's more, according to the Federal Communications Commission, about 15 million to 20 million households are overcharged for their telephone landlines by third-party companies but only 5 percent realize they are victims.
One FCC investigation found that only 22 of 18,571 consumers surveyed used the third-party dial-around long distance service for which they were billed -- roughly a 0.1 percent usage rate.
A sample bill courtesy of the Senate Commerce Committee showed that third-party vendor charges appeared on page 109 of a 120-page bill. They ranged in price from $12.95 to $24.95 and used these terms:
S80-Online.org Survival Kit Montly Fee
Selected Options Inc. -- Voicemail Month Fee
Trivoice International Ltd., Voicemail Monthly Fee
United Comm. Link Monthly Voicemail Fee
Solo Communications Voicemail Monthly Fee
Traveller Info Services -- Tech Support Month Fee
Voicevox Voicemail Service Month Fee
Voiceexpress Voicemail Monthly Fee
Total Protection Plus Voicemail Month Fee
800 V Mailbox Inc. -- Voicemail Monthly Fee
And a Verizon bill from May 2010 showed that third-party vendor charges appeared on page 4 of a five-page bill and bore the labels Voicemailmnthlyfee ($14.95) and MyBillingSvcMnthly Fee ($8.23). The consumer was refunded both fees in July 2010.
How to Protect Yourself
Contact the phone company and opt out of third-party billing.
Know your phone bill. Recognize unusual charges that may be buried in the bill.
Be careful when supplying your name, address and phone number for promotions, coupons and sweepstakes.
Read all forms and promotional materials before signing up for telephone or other services.
Don't ignore small charges, which can add up to big amounts.
ABC News' Susanna Kim and The Associated Press contributed to this story.