Depth of cure of resin composites is essential for the clinical success of these materials. It has been observed that if composite is inadequately polymerized, it results in poor development of its physical properties. In the last few years, there has been a trend towards developing resin restorations which can save time during the placement step. Presently, there is a growing trend towards the use of bulk-fill materials amongst clinicians due to simplified protocol.The objective of this study was to compare the mean depth of cure of two composite materials (SDR & Filtek Bulk-fill) cured at incremental depth of 2, 4 and 6mm as determined by the ISO 4049 method at 2 different voltages i.e. 180 and 220 volts.