Lead concentrations in drinking water samples collected under various sampling protocols in homes with lead service lines and in homes without lead service lines in two US cities. This dataset is associated with the following publication: Lytle, D., M. Urbanic, A. Paul, R. Achtemeier, A. Lewis, S. Hammaker, A. Estep, M. Nadagouda, R. James, and S. Triantafyllidou. Alternative approaches to lead sampling in drinking water: A comparative study of homes with and without lead service lines in two cities. WATER RESEARCH. Elsevier Science Ltd, New York, NY, USA, 994: 180063, (2025).