A fast algorithm is developed for automatic selection and ranking all possible circuits for corrective control by network switching to relieve system overloads. The non-iterative DC approximate model for a power system is used to generate linear sensitivity factors. These factors are calculated using relevant elements of the sparse bus impedance matrix and branch reactances. Special treatment of substation circuit breakers makes it possible to use bus-bar splitting for corrective action. The method was tested on two systems. Test results show the reliability and effectiveness of the method in selecting lines and circuit breakers for corrective overload control.