WASHINGTON ( CNN ) -- Thousands of Americans learn a painful lesson in banking every day : Waiting for a check to clear and then getting access to the money from a bank does n't mean the check has really cleared . When Harry Smith , of New York , responded to an ad on Craigslist for an office assistant , a woman e-mailed him and said her British company was starting to sell its product in the United States , but was having trouble with dealing with checks from customers . Smith said the woman needed someone to collect the checks and then send the money to her company . It was a commission job -- deposit the checks , wait for the funds to become available at his bank , then send cash to her , minus 10 percent for Smith . After Smith checked out what seemed like a legitimate company on the Internet , he started receiving checks totaling several thousand dollars and deposited them in his account . When his bank released the funds , he sent cash to an address outside the country . But after a few weeks , Smith 's bank notified him the checks he had deposited had actually been returned , and that he owed the bank all the money he had withdrawn . Smith has not heard from his business partner since and does n't even know who she really is . He still owes his bank money , is unemployed and does n't know what action the bank might take against him . What happened to Smith is one example of a wide range of fake check scams carried out in the United States every year . A Consumer Federation of America survey estimates that 1.3 million Americans have been the victim of a fake check scam , with an average loss of $ 3,000 to $ 4,000 per consumer . The most common scams are fake sweepstakes or lotteries , phony government sponsored grants and fraudulent work-at-home opportunities , the survey says . The scams follow the pattern of the so-called Nigerian Internet scams , which often involve accepting transfers of money that become obviously phony when it 's too late . On Wednesday , the Consumer Federation launched a campaign to combat check scams . Many consumers do n't know they are responsible if they deposit a bad check , said Susan Grant , the federation 's director of consumer protection . Grant said its survey shows an alarming level of misinformation among consumers , and the problem includes money orders and cashier 's checks . Fifty-nine percent of respondents in the survey incorrectly thought that , when you deposit a check or money order , your bank confirms it is good before allowing you to withdraw the money . That number goes up to 70 percent among adults age 18 to 24 . More than 40 percent of those surveyed also incorrectly think that the person who gave you the bad check must pay back the bank . American consumers are mostly unfamiliar with the time needed to process checks and money orders , say consumer watchdogs . Government banking rules mandate that money from deposits become available within one to five days . However , it can take weeks , especially with foreign checks or money orders , for the originating institutions to get the checks or money orders back and determine that they are counterfeit . When that happens , scam victims are in for a rude surprise . Publishers Clearing House , which runs legitimate sweepstakes , warns consumers that scammers might claim that you are being given an advance on a prize , but that some fee , tax or other payment needs to be sent before you get the jackpot . That 's the heart of the scam , and it 's something that a real sweepstakes will never ask for , say legitimate companies . Consumer protection groups , state attorney generals , the Federal Trade Commission and government bank regulators warn consumers that the number of fake checks , money orders and even cashier 's checks being used to scam victims is increasing . The bottom line : `` There 's no legitimate reason why anyone who wants to give you a check or money order for something would ever ask you to send money anywhere in return . It 's as simple as that , '' said Grant of the Consumer Federation of America . Smith said he suspected that his part-time job was not on the up-and-up , but did n't know about fake check scams . He 's not sure how he will pay back his bank , but hopes his story will help keep other people from becoming victims . The Consumer Federation of America 's tips against fake check scams : . -- Never agree to pay to claim a prize . -- Never agree to pay for grants from the government or foundations . -- Never agree to cash checks and send the money somewhere as part of a job working from home . -- Never agree to wire money to anyone you have not met in person and known for a long time . -- If it seems suspicious , consult your state or local consumer protection agency , the Federal Trade Commission , the U.S . Postal Inspection Service or another trusted source . -- Remember that there is no legitimate reason why anyone who wants to give you a check or money order would ask you to send money anywhere in return .
More than 1 million people have been victims of fake check scams , study says . Experts warn not to accept money from someone expecting money in return . Time : Most American consumers unfamiliar with time needed to write checks .