A surgical access assembly includes a cannula and a retention anchor including an annular body and a washer secured to the annular body. The annular body includes an inner side surface defining an opening therethrough, and the washer includes an inner terminal edge defining an opening therethrough that is aligned with the opening of the annular body. The elongated shaft of the cannula extends through the openings. The washer is transitionable between a first configuration in which the inner terminal edge of the washer is coincident with or disposed radially outwardly of the inner side surface of the annular body so that the retention anchor is slidable along the elongated shaft, and a second configuration in which the inner terminal edge of the washer extends radially inwardly of the inner side surface of the annular body and engages the elongated shaft to fix the retention anchor to the elongated shaft.