Yardville, NJ has a population of 7,147 and is the 5,106th largest city in the United States. The population density is 1,757 per sq mi which is 175611% higher than the New Jersey average and 1839% higher than the national average. The median age in Yardville is 47 which is approximately 18% higher than the New Jersey average of 40. In Yardville, 60% of the population over 15 years of age are married, 92% speak English and 1% speak Spanish. 79% of Yardville residents were born in New Jersey, 15% were born out of state, 1% were born outside of the United States and 5% were foreign born.