BACKGROUND: There is little evidence supporting the use of a water-soluble contrast challenge (WSCC) for conservative management of nonadhesive small bowel obstruction (NASBO). Our objective was to evaluate the prognostic value of the WSCC in a diverse group of patients with NASBO in comparison with patients with adhesive small bowel obstruction (ASBO). STUDY DESIGN: Retrospective chart review of patients with ASBO or NASBO who underwent a WSCC during a 4-year time period was performed. The primary study endpoint was any intervention for small bowel obstruction during the initial admission or within 30 days of discharge. RESULTS: A total of 106 patients were included, 53 with ASBO (mean age 64 ± 13 years [SD]; 55% women) and 53 with NASBO (mean age 59 ± 13 years [SD]; 57% women). A higher rate of interventions during admission or within 30 days of discharge was seen in patients with NASBO compared with ASBO (24/53 [45%] vs 12/53 [23%]; p = 0.01), including those with colonic transit times of less than 36 hours (14/41 [34%] vs 5/43 [12%]; p = 0.01). Using multivariate analysis, transit time greater than 36 hours remained an independent predictor of an intervention during admission or within 30 days of discharge (p < 0.001, odds ratio 19.0), after controlling for the type of small bowel obstruction. CONCLUSIONS: A majority of patients with NASBO were successfully managed conservatively during a 30-day period, supporting the use of WSCC in patients with NASBO; however, patients with NASBO had a higher rate of interventions during admission or within 30 days of discharge.