Timing of chest tube (CT) removal after transition from suction to water-seal (WS) varies when treating traumatic simple pneumothoraces (PTXs). Longer periods of WS may identify slow-occurring PTXs reducing CT replacement, whereas shorter periods may expedite patient disposition and have associated cost savings. Prior studies support the need for an interval of WS. We compare durations of WS, looking at rates of CT reinsertion. A 10-year retrospective review on trauma patients with a simple PTX requiring a CT was performed. WS duration of 1 to 8 hours (short - SG) versus 18 to 36 hours (long - LG) were compared. Univariate analysis and multivariate logistic regression were used. Of the 2000 patient charts reviewed, 209 met the criteria, with 43 in the SG and 166 in the LG. Patient demographics and mechanism of injury were similar. There was no difference in CT replacement [6.9% (SG) vs 4.8% (LG), P 0.59]. Logistic regression revealed an increase in CT replacement if the patient ever had positive pressure ventilation (OR 4.1, CI 1.1-17, P 0.04) and if returned to suction from WS (OR 6.3, CI 1.2-28, P 0.03). Short intervals of WS do not increase CT reinsertion while decreasing the total time and morbidity associated with CT.