Accurate determination of hydrate formation conditions and water content of natural gas systems is critical for cryogenic processes used in the production of natural gas liquids (NGL), liquefied natural gas (LNG) processing, and carbon dioxide (CO2) capture. Water content of three natural gas mixtures was measured in this work using a Panametrics moisture analyzer at low temperatures and pressures up to 40 MPa. The statistical associating fluid theory (PC-SAFT) combined with a modified van der Waals and Platteeuw (vdWP) theory was used to model the system phase behavior. The theory was found to be in good agreement with experimental data, thus exhibiting the predictive ability of the proposed model.