School Non-Attendance Among Children and Adolescents in Ecuador: Socioeconomic, Territorial, and Age-Related Inequalities from a Nationally Representative Survey

School non-attendance remains a major expression of educational inequality, yet nationally representative evidence on its socioeconomic and territorial distribution in Ecuador is limited. This study examined factors associated with school non-attendance among children and adolescents aged 5–17 years using the 2025 National Survey of Employment, Unemployment and Underemployment (ENEMDU). A cross-sectional secondary analysis included 69,423 participants. Weighted prevalence estimates, design-adjusted tests, survey-weighted logistic regression, and adjusted marginal probabilities were calculated while accounting for the complex sampling design. The weighted prevalence of non-attendance was 5.22% (95% CI: 4.71–5.79). In the adjusted model, rural residence was associated with higher odds of non-attendance than urban residence (aOR = 1.80, 95% CI: 1.43–2.26), and poverty was associated with higher odds than non-poverty (aOR = 1.92, 95% CI: 1.57–2.35). Age showed a significant non-linear association, with elevated adjusted probabilities at age 5 (11.75%, 95% CI: 8.47–15.04) and ages 15–17 (12.92%, 95% CI: 11.67–14.17) but lower probabilities at intermediate ages. No sex differences were significant. These findings reveal socioeconomic, territorial, and age-related inequalities and support territorially responsive policies to promote timely school entry and adolescent retention. Given the cross-sectional design, the results represent associations rather than causal effects.