We investigated the intra- and inter-site reproducibility of 1H-MRS with short-TE PRESS at 3T acquired on a single manufacturer at 6 different sites. Metabolite concentrations were robust to small inconsistencies in voxel placement (mean alignment=86%), highlighting that site was not the driving factor for differences in metabolite concentrations. Between-subject differences drove the concentration variability for creatine, choline and myoinositol (42-65% of the variance). The mean intra-site coefficient of variation for the metabolites was between 2.5% and 5.3%. The results support the use of a large single voxel 1H-MRS acquisition from a single manufacturer for multi-site clinical trials.