Context: Balance is important for injury prediction, prevention, and rehabilitation. Clinical measurement of higher level balance function such as hop landing is necessary. Currently, no method exists to quantify balance performance following hopping in the clinic. Objective: To quantify the sacral acceleration profile and test–retest reliability during hop landing. Participants: A total of 17 university undergraduates (age 27.6 [5.7] y, height 1.73 [0.11] m, weight 74.1 [13.9] kg). Main Outcome Measure: A trunk-mounted accelerometer captured the acceleration profile following landing from hopping forward, medially, and laterally. The path length of the acceleration traces were computed to quantify balance following landing. Results: Moderate to excellent reliability (intraclass correlation coefficient .67–.93) for hop landing was established with low to moderate SEM (4%–16%) and minimal detectable change values (13%–44%) for each of the hop directions. Significant differences were determined in balance following hop landing from the different directions. Conclusion: The results suggest that hop landing balance can be quantified by trunk-mounted accelerometry.