Minor sequelae, such as pain, nausea, and drowsiness, often occur in surgical outpatients in the immediate postdischarge period. In this prospective, observational study was defined the daily incidence and intensity of several symptoms during the first week after surgery and determined predictive factors of minor morbidity. In two similar mixed ambulatory surgery units, 3910 patients received a questionnaire to grade daily the intensity of predefined symptoms on a 4-point scale. Multinomial logistic regression was used to analyze risk factors, with adults and children as separate groups. Of these patients, 2754 (70%) responded. Patients experienced numerous minor sequelae during the first week after ambulatory surgery. Symptoms were common (up to 86% of all patients) on the initial days after surgery and were still reported by 24% of adults on the postoperative Day 7. In adults, pain was the most common symptom and, in comparison with other symptoms, was more often moderate or severe. Drowsiness was most common in children. Younger adults, older children, and women were more prone to experience minor morbidity. Longer duration of surgery led to increased likelihood of pain and nausea in all patients and increased the risk of several other symptoms in adults.