It's one of the million little things you need to do when you move—contact the postal service to change your mailing address.
Here's where the problem can occur: Many people do a random search for "address change" and wind up on one of a number of sites run by private businesses. These companies charge anywhere from $17 to $24 to file that simple change of address form for you, something you can do yourself on the official USPS site for a dollar.
Scambook.com, an online complaint resolution site, has heard from hundreds of consumers about such "change of address" sites.
"Some people report they are charged $1.00 at first, but then a short time later, there's another charge for additional services they did not knowingly purchase," said Scambook's Miranda Perry.
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Most of these complaints are about a site called Change-My-Address.com. The company's Google Search advertisement appears at the top of the list when you search terms like "forward my mail," "change my address," register new address" or "USPS change of address."
Angela Leddy went online to change her address after her recent move to a new house in Indianapolis. She searched for "change my mailing address" and saw an ad that said "USPS® Change of Address Form. Fast & Secure Mail Forwarding."
She clicked on the link and landed on Change-My-Address.com. Thinking she was on the U.S. Postal Service site, Leddy filled out the form and punched in her credit card number.
Two days later, Leddy spotted a $19.99 charge on her account. And she was furious.
"It's deceitful, it's deceptive and it's misleading," she said. "And for someone who's pretty Internet savvy, I was scammed."
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Leddy called the company and they agreed to refund $10. Not satisfied with that partial refund, Leddy complained to the Better Business Bureau of Cincinnati (where the company is located), which got the company to refund the rest of her payment.
The BBB has received more than 150 complaints in the last year about Change-My-Address.com.
"That's a lot of complaints for one company," said Leslie Kish, vice president of operations at the Cincinnati BBB. "There is a pattern of complaints about customer service and refund issues. Some people said they paid the money and did not receive the change of address service."
Change-My-Address has an F rating with the Better Business Bureau.
In a statement emailed to NBC News, Change-My-Address.com said it addresses all complaints and offers a partial refund of $10 to anyone who requests it within 10 days.
"We have worked since our inception to be in compliance with all local, state and federal laws," Benjamin Miller in corporate communications wrote. "We have attempted to work with our local Better Business Bureau, unfortunately with little success. However, we answer all complaints with the BBB and have a positive resolution rate better than 97 percent."
The company said it gives its "members" generous value-added services for that $19.95 fee, such as special offers from major retailers.