Objective: Childhood- and adolescent-onset epilepsy may have a significant impact on long-term educational and vocational status, which in turn has consequences for individuals' socioeconomic status. We estimated the factual long-term socioeconomic consequences and healthcare costs of individuals with diagnosed epilepsy. Methods: The prospective cohort study included Danish individuals with epilepsy onset before the age of 18 years, diagnosed between 2002 and 2016. Healthcare costs and socioeconomic data were obtained from nationwide administrative and health registers. The prediction was made with a general estimating equation (GEE). A total of 15,329 individuals were found with the diagnosis during this period and were followed until the age of 30 years. These were compared with 31,414 controls. We used 30 years as this represent an age where most has finalized their education, and as such represent the final educational level. Patients and their controls were subdivided into debut age groups of 0–5 and 6–18 years. Individuals were matched for age, gender, and residential location. Results: Compared with control groups, patients with epilepsy at the age of 30 years tended to have the following: 1) parents with lower educational attainment; 2) a significantly lower educational level when controlling for parental education attainment; 3) lower grade-point averages; 4) a lower probability of being in employment and lower income, even when transfer payments were considered; and 5) elevated healthcare costs, including those for psychiatric care. It was also noted that the long-term educational consequences for patients with epilepsy were associated with parental educational level. Differences were more pronounced for those with early (0–5 years) rather than later (6–18 years) onset epilepsy. Conclusions: Epilepsy is associated with severe long-term socioeconomic consequences: lower educational level, school grades, employment status, and earned income. The presence of epilepsy is associated with parental educational level. Limitations: 1. Register-based study; epilepsy based on diagnosis within the hospital sector; patients found with diagnosis in general practice were not included. 2. Some patients treated in the primary sector may not have been identified. 3. Parental education level may have risen after the index date when the patient was first included. Significant outcomes: • Childhood and adolescent epilepsy are associated with long-term negative impacts on educational level, employment status, and earned income. • Childhood and adolescent epilepsy are associated with long-term healthcare uses, especially for those with early disease onset. • Childhood and adolescent epilepsy are related to lower levels of parental education.