Palmyra, IL has a population of 579 and is the 18,658th largest city in the United States. The population density is 580 per sq mi which is 161% higher than the Illinois average and 540% higher than the national average. The median age in Palmyra is 45 which is approximately 20% higher than the Illinois average of 37. In Palmyra, 55% of the population over 15 years of age are married, 99% speak English and 1% speak Spanish. 91% of Palmyra residents were born in Illinois, 7% were born out of state, 1% were born outside of the United States and 0% were foreign born.