Left ventricular (LV) mass is a major determining tool for myocardial injury in hypertensive patients. Issues with LV mass calculations exist given that there are multiple methods to assess mass, including from the parasternal long axis (PLA), parasternal short axis (PSA), and 2-dimensional (2D) volumetric methods. The aim of this study was to compare the agreement of LV mass calculations using the PLA, PSA, and 2D volumetric methods. This study retrospectively reviewed 200 consecutive, initial echocardiograms for the indication of hypertension. A single reader calculated the LV mass in each patient via the PLA, PSA, and 2D volumetric methods. Percent differences for each study were calculated. LV mass threshold cutoffs of 51 g/m2.7 (cardiac organ injury) and 38.6 g/m2.7 (elevated LV mass) were used to compare categorical differences between the different measurement methods. Paired comparisons demonstrated an absolute mean percent difference of 8.46% to 9.41% among the different methods. LV mass calculated by the 2D volumetric method was less compared with PLA and PSA methods (31.64 vs 33.90 vs 35.51 g/m2.7; p < 0.0001). Fewer patients were classified as having cardiac target organ injury or elevated LV mass via 2D volumetric calculation, compared with PLA and PSA methods (p = 0.02 and p = 0.03, respectively). In conclusion, there is a small but important difference in LV mass calculations for patients with hypertension. These results emphasize the need for consistency within echocardiography laboratories as surveillance studies are common in this patient population.