We present an experimental study of the superconducting properties of NiBi3 as a function of pressure by means of resistivity and magnetization measurements and combine our results with density functional theory calculations of the band structure under pressure. We find a moderate suppression of the critical temperature [Formula: see text] from [Formula: see text] [Formula: see text] K to [Formula: see text] [Formula: see text] K by pressures up to 2 GPa. By taking into account the change of the band structure as a function of pressure, we argue that the decrease in [Formula: see text] is consistent with conventional, electron-phonon-mediated BCS-type superconductivity.