Definition: A non-paying bidder (NPB for short) is a bidder who has won an auction, either by placing the winning bid or by using the Buy It Now button, but who refuses to pay for that auction according to the auction terms. eBay auctions are binding contracts, and bidders are thus legally responsible for completing transactions once they have won an auction.
In the absence of specific time guidelines, a seller can file a complaint if payment has not been received within ten days of auction close. The bidder must, however, comply with any additional or more stringent terms set forth in the auction listing.
Note that a bidder can be considered non-paying if he or she fails to complete the auction for any reason, including the inability to pay using the method required in the auction.
Multiple non-paying offenses by a bidder may lead to disciplinary action from eBay. Sellers are also known to leave rather scathing negative feedback for non-paying bidders.
