This study investigated teacher and parent ratings of teacher-nominated gifted elementary school students’ verbal abilities, mathematical abilities, deductive reasoning, creative thinking, and engagement, and connected these ratings to school grades. Teacher and parent ratings were compared with regard to accuracy levels and halo effects. Furthermore, this study explored the correlations between teacher and parent ratings and how they are related to school grades. The study was based on data from 572 elementary school students participating in an enrichment program. The results indicated the same accuracy levels for teachers and parents. However, teacher ratings were more strongly affected by halo effects than parent ratings. The correlations between teacher and parent ratings were small to medium. Both raters’ ratings were independently and positively associated with German grades when controlling for each other. Positive teacher or parent ratings of mathematical abilities and engagement buffered the relation between the other rater’s ratings and math grades.