ObjectivesTo assess all-cause mortality and suicides after pediatric traumatic brain injury (pTBI). Study designWe conducted population-based historical cohort study using three nationwide registers from 1998 to 2018 in Finland. All patients that were the age of 0–17 at the time of the pTBI were included. The reference group consisted of children with ankle or wrist fractures. We used Kaplan–Meier and restricted mean survival time (RMST) analysis with 95% confidence intervals (CI) to compare all-cause mortality and suicides between groups. ResultsAfter 20 years of follow-up, there were 479 deaths in the pTBI group (0.67% of 71,963) and 306 deaths in the reference group (0.47% of 64,848). In the pTBI group, 28.6% of the deaths occurred after the first follow-up year, compared to 2.6% in the reference group. In all-cause mortality, survival time was slightly less in the pTBI group with age and gender adjustment throughout the follow-up period [20-year RMST ratio: 0.995; CI (0.994–0.996)]. The leading manners of death were suicides (pTBI group = 28.4%; reference group = 45.5%) and traffic collisions (pTBI group = 37.4%; reference group = 20.8%). Age and gender-adjusted survival time was slightly less for those with suicide as a manner of death in the pTBI group [10-year RMST ratio: 0.999; CI (0.999–0.999); 20-year RMST ratio: 0.999; CI (0.998–0.999)]. ConclusionsChildren and adolescents who sustained a TBI have slightly lower long-term survival time for all-cause mortality, most of which occurs during the first year following injury. There is no clinically meaningful difference in deaths by suicide between the two injury groups.