The second order nonlinear refractive index n 2 of various multicomponent glasses was measured at the wavelength of 1240 nm close to the 1.3-μm fiber transmission window. With the refractive index covering the range from 1.45 to 2.3, a comparatively broad range of n 2 with values from 1.1×10−20 m2/W for boro-silicate based glass NC21 to 4.3×10−19 m2/W for lead–bismuth-gallate based glass PBG08 was measured using the Z-scan method. Considering the broad infrared transmission range of multicomponent glasses, these materials pose a great potential for future applications as photonic crystal fiber sources of infrared supercontinuum.