The aim of the study was to measure the force deflection behavior of 3 different dimensions of 5 commercially available brands of orthodontic arch wires used in initial stages of orthodontic treatment, with use of a universal testing machine. 20 samples of 3 different dimensions of 5 brands wires were tested, so total of 300 wires were tested. Four standard metallic pre adjusted edge wise brackets (0.022”) were attached to a acrylic jig in order to simulate clinical scenario. The test was carried out with a crosshead speed of 1 mm/min to a depth of 2 mm. Load deflection graph was plotted for each sample. Results showed that, deactivation forces varied among the different commercially available brands of nickel titanium wires and variation was found in the same dimension of wires between different brands. GAC orthodontic archwire produced least and efficient force during loading and unloading for all 3 dimensions of wires tested. The deactivation force was found to be least in 0.014” GAC orthodontic wire, suggesting it to be suitable choice during initial stage of treatment as it produces low and continuous force following 0.014” AO archwire.