Abstract Introduction Soldiers have a higher risk for developing psychiatric disorders that require treatment; often with antidepressants. However, antidepressants as well as the psychiatric disorder, may influence military readiness in several ways. In the general population, early discontinuation of antidepressant treatment is often seen. It is yet unknown whether this occurs to a similar extent in soldiers. The objective of this study was to evaluate discontinuation of antidepressant use by Dutch soldiers in the first 12 months after start and determinants thereof. Materials and Methods Data were obtained from the military pharmacy. All Dutch soldiers who started using an antidepressant between 2000 and 2014 were included. Kaplan–Meier curves were constructed to estimate the discontinuation rate over time and the influence of each determinant on discontinuation rate was estimated using Cox regression. Results About 25.9% of de 2479 starters had discontinued their antidepressant use after 1 month; after 3 and 6 months this number increased to 52.7% and 70.3%, respectively. Early discontinuation was higher in soldiers who received their first prescription from a neurologist or rehabilitation specialist (HR 1.85, 95% CI 1.55–2.21, HR 2.66 95% CI 1.97–3.58) compared to soldiers with a first prescription from a general practitioner. In addition, early discontinuation was lower in soldiers who were prescribed serotonin reuptake inhibitors and other antidepressants (HR 0.57, 95% CI 0.51–0.60, HR 0.63, 95% CI 0.55–0.73) and in soldiers between 40 and 50 years of age (HR 0.79, 95% CI 0.70–0.89). Conclusion More than half of the soldiers discontinued their prescribed antidepressant within 3 months and after 6 months, only 30% were still on antidepressants.