Physical inactivity is currently a significant problem in Western societies. Among the many factors that affect the amount of physical activity in children, socioeconomic status, the type of school, and the area where they live can play a major role in physical development. A total of 31,620 children (6.3 ± 0.53 years; 15,726 boys; 15,893 girls), representing 55.6 % of the entire Slovak population of first graders, participated in eight motor performance (MP) tests, the results of which were correlated with somatic parameters (body height, body weight, and body mass index (BMI)) and socioeconomic indicators (SEIs) within the children’s respective territorial regions. The largest correlations were observed between MP and unemployment rate (r = −0.802) and between MP and economically active population with primary education (r = −0.807). Other correlations between MP and SEIs were also found at the level of self-governing regions (r = 0.995) and districts (r = 0.551). SEIs and MP were strongly correlated, indicating that children who grow up in better socioeconomic environments display greater MP. Therefore, national and local governments should provide tangible and intangible resources to enable the proper development of children’s MP.