The L-band synthetic aperture radar (L-SAR) aboard the joint NASA/Indian Space Research Organization SAR (NISAR) mission is a side-looking, fully polarimetric, interferometric synthetic aperture radar operating at a wavelength of 24 cm. The radar is capable of 242 km swaths, 7 m resolution along track, 2-8 m resolution cross-track (depending on mode) and can operate in various modes including quadpolarimetric modes, i.e. transmitting in both vertical and horizontal polarizations, and receiving in both the same polarizations transmitted, and cross-polarizations. From the NISAR science orbit, the instrument's pointing accuracy is such that the L-SAR data can be used to produce repeat-pass interferograms sensitive to large-scale land deformation rates as small as 4 mm/year. The L-band SAR will be heavily utilized during the mission, with current mission scenarios having the instrument on and collecting data for 45-50% per orbit on average, with peaks as high as 70%.