New density and viscosity results for 2,2,4-trimethylpentane at temperatures from 198 K to 348 K and pressures up to 100 MPa are reported. The measurements of both properties were performed simultaneously using a vibrating-wire instrument operated in the forced mode of oscillation. The present set of measurements extends those found in the literature to the high-pressure and low-temperature region. Correlations for both the density and the viscosity are presented, and comparisons are established with various sets of results from the literature. The estimated uncertainties of the results are ±0.05% for the density and ±2.5% for the viscosity.