Essex is a city in Stoddard County, Missouri, United States.According to the United States Census Bureau, the city has a total area of 0.29 square miles (0.75 km2), all land.33.7% of all households were made up of individuals, and 14.3% had someone living alone who was 65 years of age or older.Public education in Essex is administered by the Richland R-1 School District.[10] Students consistently score above the state averages administered by the Missouri Department of Elementary and Secondary Education.