The rate of small bowel obstruction (SBO) after colectomy is unknown. Given the large number of colectomies performed in the United States, elucidating SBO rates, outcomes, and identifying predictors of readmission is important. Using the California Inpatient File, we identified all patients readmitted with a principle diagnosis of SBO at least once in the 3 years after colectomy (n = 4555). Patients admitted with a diagnosis of SBO in the 3 years before surgery were excluded. Overall, 10 per cent of patients were readmitted for SBO at least once after colectomy. Approximately 58 per cent were readmitted in the first year and 22 per cent of these patients required surgery. The most common operation performed was lysis of adhesions. Median length of stay was twice as long in the surgery group versus the no surgery group (12 vs 6 days). Overall mortality was higher in the nonsurgery group compared with the surgery group (33% vs 21%, P < 0.001) and highest in the elderly (44% vs 30%, P < 0.001). One in 10 patients without a history of SBO who undergoes a colectomy will be readmitted at least once in the subsequent 3 years for SBO, and there is a high mortality rate in this group, especially in the elderly.