Establishing breeding programs that improve farmed fish performance across multiple environments is crucial in a globalized aquaculture market. The main objectives of the current study were to assess the growth performance of genetically improved farmed tilapia (GIFT) under different environments, across 3 different countries (Malaysia, India, and China), termed genotype by environment interaction (G × E) or macro-environmental sensitivity, and to quantify the genetic heterogeneity of environmental variance for body weight at harvest (BW) in GIFT, as a measure of micro-environmental sensitivity or robustness.