In this paper, phase equilibrium and viscosity data were experimentally obtained for a CO2 + n-dodecane (n-C12H26) binary mixture. The experiments, which were conducted with a custom-made PVT cell of variable volume connected to an oscillating-piston viscometer, considered CO2-based mixtures with mole fractions between 0.2 and 0.8, and temperatures spanning from 283 to 353 K. The experimental tests were complemented with theoretical analysis, which relied on the Peng-Robinson, PC-SAFT, and PCP-SAFT equations of state (EoS) to correlate the bubble point pressure, while the friction theory (f-theory) coupled to either the Peng-Robinson or the PC-SAFT EoS was used to correlate the measured viscosity. The analysis revealed that the smallest absolute deviations for the bubble point pressure and viscosity, respectively, are 2.2 and 8.51%, and were obtained with PCP-SAFT EoS and f-theory/PC-SAFT.