Best SEO and internet marketing services in Yates County NY. Yates County zip codes - 14415, 14441, 14478, 14507, 14527, 14842, 14857 Yates County is a county in the U. S. state of New York. It is located in the middle-western part of the New York State. The county was founded on February 5, 1823. Before that the county was a part of Albany County in 1683. It was named after Joseph C. Yates (a Governor on New York). Yates County’s seat is a town of Penn Yan. The largest town in the county is Milo. Total area of the county is 376 sq mi (874 sq km). Where land is 338 sq mi (875 sq km) and water is 38 sq mi (98 sq km). Water comprises 10% of the territory. There live 25,348 residents according to the census in 2010. The density is 75/sq mi (29/sq km). It is the third least populous county in New York State. There is one college in the county. It is Keuka College. Also there is one airport: Penn Yan Airport. Most of the residents are White Americans (97%), but there also live African Americans, Native Americans, Asians, Pacific Islanders, Spaniards, Italians, Germans, and others. There are several towns in the county, four villages, a census-designated place and four hamlets located in Yates County.