East Islip, NY has a population of 13,853 and is the 3,023rd largest city in the United States. The population density is 3,484 per sq mi which is 871% higher than the New York average and 3746% higher than the national average. The median age in East Islip is 41 which is approximately 8% higher than the New York average of 38. In East Islip, 62% of the population over 15 years of age are married, 93% speak English and 4% speak Spanish. 90% of East Islip residents were born in New York, 5% were born out of state, 1% were born outside of the United States and 3% were foreign born.