A numerical integration method is devoloped to calculate the intensity profile of an ultrasonic beam reflected from a liquid–solid interface. This numerical treatment is used to calculate nonspecular reflectivity at a range of angles of incidence near and at the Rayleigh angle. Calculations for a water–stainless steel interface are compared to a known approximate analysis for various beamwidths and frequencies. The theoretical predictions of the reflected beam profile near the Rayleigh angle of incidence are compared to experimental results.