Plattsburg, MO has a population of 2,299 and is the 10,260th largest city in the United States. The population density is 638 per sq mi which is 639% higher than the Missouri average and 605% higher than the national average. The median age in Plattsburg is 43 which is approximately 11% higher than the Missouri average of 38. In Plattsburg, 60% of the population over 15 years of age are married, 95% speak English and 4% speak Spanish. 68% of Plattsburg residents were born in Missouri, 29% were born out of state, 0% were born outside of the United States and 3% were foreign born.