Fast neutrons from cosmic-ray muons are an important background to underground low-energy experiments. The estimate of such a background is often hampered by the difficulty of measuring and calculating neutron production with sufficient accuracy. Indeed substantial disagreement exists between the different analytical calculations performed so far, while data reported by different experiments are not always consistent. We discuss a new unified approach to estimate the neutron yield, the energy spectrum, the multiplicity, and the angular distribution from cosmic muons using the Monte Carlo simulation package FLUKA and show that it gives a good description of most of the existing measurements once the appropriate corrections have been applied.