In the last decade financial markets haves shown a great transformation that has failed to reduce the high rate of existing banking even the current financial crisis. This high level of competition means that financial institutions are concerned about the loyalty of their customers to maintain or increase market share and profitability. In this paper we propose a statistical model that measures the risk of customer dropping out of a Spanish financial institution, and this is a widely method for the financial sector in general. The risk depend son socio-demographic, economic and, most importantly, the levels of satisfaction and customer confidence with the bank. Research shows that the proposed model can help institutions to know which customers have a greater risk of dropping out to establish, and some recommendations for their loyalty.