Cloud computing is the new business paradigm introduced in the IT market in the current decade providing the customers with the option to pay for the amount of service utilized. Cloud data storage redefines the security issues targeted on customer's out-sourced data (data that is not stored/retrieved from the costumers own servers). In this work we observed that, from a customer's point of view, relying upon a solo SP for his outsourced data is not very promising. In addition, providing better privacy as well as ensuring data availability can be achieved by dividing the user's data block into data pieces and distributing them among the available SP s in such a way that no less than a threshold number of SP s can take part in successful retrieval of the whole data block. In this paper, we propose an efficient and economical multi-cloud storage (EEMCS) model in cloud computing which holds an economical distribution of data among the available SPs in the market, to provide customers with data availability as well as secure storage. Our results show that, our proposed model provides a better decision for customers according to their available budgets.