Abstract Ab initio Density Functional calculations for free Pbn (n = 3 - 14), NanPb and NanPb4 clusters are reported. In the case of pure lead clusters, stability maxima are found for Pb7 Pb10 and Pb13, in agreement with the experimental abundance found in the mass spectra. A trend governed by icosahedral-like packing explains the ground state geometries. In the case of mixed sodium-lead clusters, high stability is predicted for Na4Pb and Na4Pb4, giving a hint for the presence of those units in the liquid alloys. A transition between a rhombus and a tetrahedral arrangement occurs in Pb4 as a consequence of adding Na atoms to that unit.