This paper is on preventing multiple opening of bank account as a security measure, to enforce the Nigeria apex bank cash-lite policy on raw cash transaction limits and the associated penalties. The paper therefore presents a remedy to stabilise and achieve the purpose of the new cash-lite policy in Nigeria economy. The Nigeria apex bank on January 1, 2012 kicked off Nigeria’s cash-lite policy using Lagos as pilot city. As a result, companies registered with the Corporate Affairs Commission (CAC), who before now operated two accounts namely, corporate current account and an individual savings account, opened accounts in virtually all the banks in Nigeria. The account users see the multiple opening of bank account as the remedy to circumvent the charges attached to exceeding daily cash transaction on both individual and cooperate bank accounts. This informed the proposition of Bayes’ theorem, to centrally monitor, control and checkmate the customers’ multiple opening of bank account at account opening desk. The Bayes’ theorem is used to check each account items/particulars submitted by the account owner/user at the account opening desk, to check if it is existing already, using each items’ given value stored in the database to calculate the probability of existence of such an account. The result which is probability of ‘X’ (P(X)) calculated where less than 0.5 ((that is if P(X) < 0.5)) would allow the continuation of the account opening process, otherwise (if P(X) >= 0.5) it will alert that the account is already existing and would prevent further opening of such an account. Results generated using Bayes’ theorem shows that customers having high number of particulars equivalent with the existing customers’ stored information will have high chances of existence, while those with less particulars will have low chances. Keywords: Cash-lite, Cash-less, Multiple account, Bayes’ theorem, Apex Bank, Central Bank of Nigeria (CBN).