BACKGROUNDOptimum excision margins used in the removal of intermediate thickness melanomas remain unclear.OBJECTIVEThis study's aim was to compare the clinical outcomes of 1-cm margins with 2-cm margins in patients with a tumor thickness of 1.1- to 4.0-mm.MATERIALS AND METHODSThis was a retrospective study, which was based on a matched-pairs design. Equal patient cohorts were constructed in terms of gender, age, Breslow thickness, and the anatomic location of the primary lesion. There were 80 patients whom underwent an excision with a 1-cm margin and 80 patients with a 2-cm margin. Follow-up data were analyzed by the Kaplan-Meier method and a Cox regression model.RESULTSAfter a median follow-up time of 41 months, there were no differences in relapse-free survival or melanoma-specific survival between study groups. The wound was closed directly in 62 patients (78%) in the 1-cm group and in 36 patients (45%) in the 2-cm group (p < .001).CONCLUSIONA 1-cm excision margin may be sufficient in melanomas of 1.1 to 2.0 mm in Breslow thickness based on these findings of low recurrence. With thicker tumors (2.1-4.0 mm), this recommendation cannot be given due to inherent study limitations.