Olmsted is a community located in the U.S. state of Illinois. It is within Pulaski County adjacent to the Ohio River. It has a total area of 3.49 square miles at 37°10′51″N 89°5′11″W. As of the 2010 census data, it had a total population of 333. The population density was 90.94/sq mi. Estimated per capita income in 2016 was $19,162. It has Zip code 62970.