Averill Park is a census-designated place within the town of Sand Lake in Rensselaer County, New York, United States. The population was 2,098 at the 2020 census.

Sand Lake is a town in south-central part of Rensselaer County, New York, United States. Sand Lake is about 13 miles east of Albany, New York. As of the 2020 census, the population was 8,348. Within the town are three hamlets: Averill Park, Glass Lake and the hamlet of Sand Lake. Its four lakes are a source of recreation. Many commercial enterprises of the 19th century and into the 20th century relied on power generated from the Wynants Kill Creek and Burden Lake mills. The area is known for its fertile soil for grazing and agriculture.