Neutral lanthanum clusters are studied by photoionization time-of-flight mass spectroscopy, laser threshold photoionization spectroscopy, and density functional theory (DFT). Mass abundance spectra (MS) registered at multiple photoionization wavelengths in the range of 195−230 nm by single photon ionization reveal the production of all sizes, La_n (n ≥ 50), in good abundance, nullifying previously predicted low abundances for certain sizes in the 3−14 size range. Also, the MS do not reveal the extraordinary stability of any specific size, as one would expect, from previous theoretical predictions of 7- and 13-atom clusters as magic. Ionization energies (IEs) are measured for La_n (n = 2−14) clusters. DFT has been used to determine the stable geometric isomers for 2- to 10-atom clusters and to calculate their IEs. The theoretical IEs of 2−7 atom clusters are in decent agreement with their experimental values; however, the theoretical IEs are somewhat lower by ~0.4 eV for n ≥ 8 than their experimental IEs.