In a longitudinal sample from Britain, we tested if attending private, fee‐charging schools rather than non‐selective state schools benefitted children’s social–emotional development. State (N = 2,413) and private school children (N = 269) showed no differences in well‐being across adolescence, but private school children reported fewer behaviour problems and greater peer victimisation over time than state schoolers. These results were independent of schools’ selection criteria, including family background, and prior academic and cognitive performance. At age 21, private and state school students differed marginally in social–emotional behaviours, such as self‐control, volunteering, sexual conduct, and substance use. After considering schools’ selection criteria, only risk taking and age at having the first alcoholic drink differed between private and state school children, with the privately educated ones being less risk averse and drinking at younger ages than those attending state school. Our results suggest that private education adds little positive value to children’s social–emotional development.