In the prediction of software quality maintainability feature play major role. Several authors suggested many more estimation models for predicting the maintainability of the software. Here, the authors were proposed non-linear maintainability model to find the significant factors for maintainability in the systems which were shows the non-linear behavior in the nature. Understandability and modifiability are the two factors give good support to find out the maintainability. In this paper, they used t-test for reduction of the regression overhead in the process of finding the estimation model of the maintainability.