Under open access, market driven transactions have become the new independent decision variables defining the behavior of the power system. The possibility of transmission lines getting over-loaded is relatively more under deregulated operation because different parts of the system are owned by separate companies and with different parts operated under varying service charges. This paper discusses a two-tier algorithm for correcting the line over-loads in conjunction with the conventional power-flow methods. The method uses line-flow sensitivities, which are computed through the Fast Decoupled Power-flow algorithm and can be adapted for on-line implementation.