Background Correctional officers (COs) experience elevated rates of mental and physical ill-health as compared with other general industry and public safety occupations. The purpose of this study was to investigate demographic, mental health, job tenure, and work–family characteristics and their prospective association to burnout within and between jail officers during one year of new employment. Methods In 2016, newly hired jail officers (N = 144) completed self-reported surveys across four time points in a one-year prospective study at a Midwestern United States urban jail. Linear mixed-effects and growth modeling examined how work–family conflict (W-FC) and depressive symptoms relate to perceptions of burnout over time. Results Jail officer burnout increased and was related to rises in W-FC and depression symptoms. Within-person variance for W-FC (B pooled = .52, p < .001) and depression symptoms (B pooled = .06, p < .01) were significant predictors of burnout. Less time on the job remained a significant predictor of burnout across all analyses (B pooled = .03, p < .001). Conclusions Results from this study indicate that burnout increased during the first year of new employment; and increased W-FC, higher depression, and brief tenure were associated with burnout among jail COs. Future study of correctional workplace health is needed to identify tailored, multilevel interventions that address burnout and W-FC prevention and early intervention among COs.