A light emitting diode (LED) apparatus for mounting to a heat sink having a front surface with an opening therein is disclosed. The apparatus includes a sub-mount, at least one LED die mounted on the sub-mount, and a thermally conductive slug having first and second areas. The first area is thermally coupled to the sub-mount and the second area has a post protruding outwardly therefrom. The post is operably configured to be received in the opening in the heat sink and to secure the LED apparatus to the heat sink such that the second area is thermally coupled to the front surface of the heat sink. Other embodiments for mounting an LED apparatus utilizing adhesive thermally conductive material, spring clips, insertion snaps, or welding are also disclosed.