Genomic estimates of performance of dairy replacements are becoming more common on farm. Our objective was to evaluate the relationship of genomic body size estimates with heifer growth for heifers managed in confinement or on pasture. To evaluate this, heifers (n = 32) were managed in a confinement pen-based bedded pack barn (n = 16 heifers) or on pasture in a rotational grazing system (n = 16 heifers) for each grazing season with 2 grazing seasons completed (total of 32 heifers in each management setting). Heifers were blocked by weight (light or heavy) and randomly assigned to a management setting. The pasture contained a mixture of red and white clover, meadow fescue, festulolium, and ryegrass. Heifers on pasture were moved twice a week to a new paddock. A mineral/vitamin mix was provided daily, but no supplemental concentrate was provided. Body measurements were taken at the start and end of the grazing season for both confinement and pastured heifers. Heifers in confinement were limit-fed a total mixed ration to obtain growth rates of 0.8 to 1 kg/d. Genomic estimates of body size were obtained from a herd database with tissue samples previously submitted as a pre-weaned calf. Forage height measurements were taken with a rising plate meter. Available forage was then determined using 3 calibration locations taken weekly on each paddock. Forage availability was 1991 kg/ha in 2017 and 2736 kg/ha in 2018. Data for comparison of management system were analyzed using Proc Mixed (SAS v9.4) as a randomized complete block design with year as a repeated measures. Heifers grazing pasture had greater growth than those in confinement during both years (0.93 vs. 0.76 kg/d; P = 0.02). Hip height gains and body condition change during the season were similar (P > 0.34) for grazing (13.4 cm and 0.41 units) and confinement (12.7 cm and 0.23 units) heifers. Heifers raised in a managed intensive grazing system can have similar or even improved daily gains compared with heifers raised in confinement.