A new organic nonlinear optical single crystal, isonicotinamide bis-paminobenzoic acid (INBAB), is grown from methanol solution using a slow evaporation solution technique. INBAB belongs to a monoclinic system with the space group P21/n. Its relative optical transmittance and optical band gap are found to be 58% and 3.4 eV, respectively. INBAB is thermally stable up to 147°C. The laser-induced surface damage threshold for our crystal is equal to 1.2 GW/cm2 for the 1064 nm Nd:YAG laser radiation. The nonlinear refractive index, the absorption coefficient and the third-order nonlinear susceptibility of our crystal are determined using a Z-scan technique. The material demonstrates optical-limiting behaviour up to the input irradiance of around 5.63 mW. © 2016, Institute of Physical Optics. All rights reserved.