Lake Cavanaugh is a census-designated place (CDP) in Skagit County, Washington, United States. The population was 167 at the 2010 census. It is included in the Mount Vernon–Anacortes, Washington Metropolitan Statistical Area.
Based on per capita income, Lake Cavanaugh ranks 30th of 522 areas in the state of Washington to be ranked. It is also the highest rank achieved in Skagit County.