Pulse wave velocity (PWV) is a biomarker that indirectly relates to arterial stiffness, an early indicator of cardiovascular disease. Breath-hold phase contrast (PC) MRI can be used to assess PWV in the aorta, however in certain populations, breath-holds may be difficult. We present a method to measure aortic PWV using a free-breathing radially-undersampled PC sequence. Initial results show that the free-breathing PC-derived PWV measures are comparable to the measures obtained from breath-hold Cartesian PC scans. Larger cohorts are warranted to verify these findings.