It's a scam involving hundreds of millions of dollars and it can easily lure you in. In one particular case, a post office manager became suspicious and helped one victim realize he was actually a victim, before it was too late.
"They believe the scam and it's hard to convince them that they were taken," explained Postmaster William Gomez.
"They" are postal customers that Gomez sees everyday.
"You get to know your customers on a personal level and you know what they receive on monthly/weekly almost," he said.
Which is why he became suspicious when he noticed one of his customers was coming in more regularly.
"Once there was numerous pieces --several weekly express pieces going and coming from out of the country - a flag was set off an alarm immediately," Gomez explained.
The Postmaster says he began to suspect his customer had gotten entangled in a lottery sweepstakes scheme.
"When you know something, you just have a gut feeling, you have to stop this because it could be devastating to someone's financial future," Gomez added.
Sweepstakes scams are costing Americans more than $120 million a day. Thousands of people are falling victim to the promise of big winnings.
"He basically told he would be receiving a large amount of money as soon as he takes care of his end on it," Gomez said.
Gomez says eventually his customer realized it was a scam, but it took a while.
"These scammers that do this thing are so good at what they do," he warned.
Postal inspectors want all consumers to remember this advice.
"Nobody is going to require fees upfront, especially fees of several thousand dollars," said US Postal Inspector Anthony Rose.
Postal inspectors say many of the victims of foreign lottery scams are elderly. If you have older relatives or neighbors, it is advised that you discuss these schemes and make sure they realize no legitimate lottery will ever ask for money upfront.