This study examines the relationships between school poverty status, family income status, and reasoning ability for the purpose of understanding the role of school poverty on reasoning skills. Cognitive ability scores of students attending mixed-poverty schools were compared to their counterparts attending institutions with low, high, and extreme poverty. Results showed that students attending economically-integrated schools had similar reasoning skills to those attending schools with low and high poverty. The largest differences were between students attending economically-integrated schools and those enrolled in schools with extreme poverty. Irrespective of school poverty status, individual income status had a strong, significant effect on reasoning skills. In general, those who participated in the federal free-reduced lunch program possessed less advanced reasoning skills than their economically advantaged peers. Research findings have important implications for economic-integration school policies.