This study examines the predictive validity of high school grade point average and ACT® Composite score on first-year college grade point average prior to and after the onset of the COVID-19 pandemic in 2020. The findings reveal that the predictive power of high school grade point average changed significantly after 2020, suggesting that students entering college after the pandemic might be underprepared for their academic journey as indicated by their lower predicted first-year grade point average. In contrast, ACT Composite scores remained relatively stable and thus continue to be a reliable predictor of students' early success in college. The study highlights the compensatory nature of using both high school grade point average and ACT Composite scores together, emphasizing the importance of considering multiple measures for achieving accurate predictions. Because they shed light on the ability to predict first-year college grades, these findings are important both for students and for colleges: For students, understanding how high school grade point average and ACT Composite score predict first-year grade point average can help them prepare effectively and seek appropriate support if needed, ensuring a smoother transition to college. For colleges, these findings indicate that using high school grade point average without a confirming alternative measure of achievement may lead them to fail to identify students who may need additional supports.