Abstract Background: To identify patient characteristics associated with outpatient mastectomies and their outcomes. Methods: Patients diagnosed with breast cancer and treated with mastectomies in Florida in 1994 were identified from state discharge abstracts and the state tumor registry. The relationship between clinical/demographic characteristics and the odds of having an outpatient mastectomy was identified using multiple logistic regression. Outcomes were assessed by calculating the risk of being rehospitalized within 30 days of discharge. Results: Twenty percent of mastectomies were performed on an outpatient basis. Outpatient mastectomies were more likely to be performed on women who were older, who lived in higher income communities, or who were uninsured. Health insurance type was not associated with having an outpatient mastectomy. Women undergoing outpatient mastectomy were more likely to be readmitted within 30 days of discharge; however, the excess risk was very small (0.7%). Conclusions: The risks from outpatient mastectomy are small. Ongoing monitoring of outcomes and assessment of patient satisfaction are needed.