Effective mathematics education is pivotal for students’ academic achievements and future career prospects. However, traditional teaching methods are often inadequate for helping students retain mathematical concepts, emphasizing the necessity for innovative approaches such as game-based learning. This research aimed to assess the efficacy of game-based learning in bolstering the retention of trigonometry concepts among senior secondary school students. Employing a mixed between and within measures ANOVA design, the study randomly assigned 60 students (aged 15-16 years, 31 males and 29 females) to either an experimental group (n=28) receiving game-based learning or a control group (n=32) receiving traditional instruction. Data, collected through the study’s tool (Mathematics Achievement Test [MAT]) at the pre-test, post-test, and retention test stages, underwent repeated measures ANOVA analysis. Results indicated significant effects of Group [F(1, 58) = 44.081, p<.001, ?²p=.432], Time [F(1.783, 103.4) = 16.561, p<.001, ?²p=.222], and Group by Time interaction [F(1.783, 103.4) = 18.125, p<.001, ?²p=.238]. The experimental group exhibited notably higher retention scores (Time 3 mean = 74.82) than the control group (Time 3 mean = 44.38). Importantly, gender, age, and location did not significantly moderate the effectiveness of the game-based approach. In conclusion, game-based learning effectively enhances and sustains students’ retention of trigonometry concepts, irrespective of demographic variables. This study furnishes empirical validation for integrating game-based learning into mathematics education, underscoring its potential to fortify conceptual retention, and offering actionable insights for educators and policymakers alike.