The aim of this longitudinal study among 9223 students from grade 7 and grade 9 (age 13-14 and 15-16) was to assess whether immigrant status and gender are associated with the level and change (slope) in school burnout among lower secondary school students in the Helsinki metropolitan area. Ninety-seven percent of the variation in school burnout was attributable to individual factors. Both the intercept (2.3, p < 0.001) and slope (0.5, p < 0.001) of school burnout were statistically significant. The slope showed increasing school burnout from grades 7-9. School burnout increased more in girls than in boys. Initially apparent higher school burnout among students who had immigrated to Finland within the last five years compared to Finnish native students was largely accounted for by sociodemographic and school-related factors. However, there was a persistent gender by immigrant status difference in the fully adjusted model: recently (< 5 years ago) immigrated boys experienced a larger increase in school burnout, especially due to increased cynicism, than recently immigrated girls.