ChexSystems is a consumer reporting agency for bank checking and savings accounts in the United States. According to bankrate.com, 80% of financial institutions use ChexSystems before opening an account. Almost all of those institutions will refuse to open a new account if a negative report is returned. Typical activities that cause a derogatory report include bounced checks, overdrafts, NSF (non sufficient funds) activity, unpaid debts such as fees owed to banks, and fraud.
Because ChexSystems is considered a consumer reporting agency, it is subject to the Fair Credit Reporting Act which requires a free report to be given to the consumer every year. The free report should be requested to verify whether a consumer has a negative report or not. If so, the consumer should only go to non-ChexSystems banks in order to save time and hassle from denials.