A thin film transistor substrate includes; a substrate, a plurality of gate lines disposed on the substrate, a plurality of data lines disposed substantially perpendicular to the gate lines, wherein the plurality of data liens include a plurality of outermost data lines, a plurality of thin film transistors (“TFTs”) connected to the gate and data lines, a plurality of pixel electrodes connected to the plurality of TFTs, and a plurality of dummy patterns connected to the outermost data lines.