This research is aimed at increasing efficiency of cash distribution from three distribution centers delivered to 377 branches, and 3,699 automatic teller machines by using Cluster First Route Second technique. New concept of assignment problem with time window is presented in this paper for clustering. A Group Sweep Algorithm which is modified from a traditional Sweep Algorithm combined with a nearest neighbor search is also presented as the routing methodology. Application software has developedusing PHP and MySQL. AMPL with CPLEX 10.0 is used to solve the assignment problem and is perfectly embraced underneath the developed application software to allow the user friendly experience. The software allow the flexibility in changing various parameters such as, capacity proportion of each cash distribution center, speed of vehicle, service time at each branch or ATM,time window of each branch or ATM or distribution center, etc. The result shows that 11 vehicle can be reduced resulting in cost reduction in a total amount of US$195,097 annually.