Many of these services are quick, efficient, and accurate. Others will only verify checks over a certain amount if the person presenting the check has a history of using the checks with the small group of merchants who use that service. This failure to gather information outside their networks sometimes result in "false negatives," where the check is rejected, even though the account has sufficient funds, longevity, and no negative reports.
It is estimated that over 25 million U.S. citizens are currently "blacklisted" by the many check verifications agencies all over the country.
There is also a checking account validation network that can poll the results of the actual bank account. Newer systems like BetterCheck, provide a result that is based on the bank account's actual status as of that business day, rather than using the traditional identity verification and check writer's history method that excludes individuals with an open valid account, but a negative history.
Due to the increasing number of people falling into the "unbanked" category, there's been a proportionate increase in the number of new businesses and websites offering assistance to these individuals. Many of these sites offer helpful information and articles, while a few others charge a fee for their services.