Method, system and program product, the method , comprising: generating by first banking institution file comprising transaction information for funds of client transaction accounts to be transferred to or from aggregated accounts in other banking institutions in an interchange program comprising plurality of FDIC-insured and interest-bearing aggregated deposit accounts; determining/receiving a total amount of funds to be held in first banking institution in its aggregated deposit account; generating transaction information for funds to be transferred to or from the aggregated accounts in other banking institutions; determining difference between an amount comprising total of funds from the client transaction accounts of the first banking institution held in the aggregated deposit accounts in the other banking institutions and total of funds held in the aggregated deposit account in the first banking institution; determining transfer information to deposit or to withdraw funds, based at least in part on the difference.