The Village of Chaumont is in the western part of the Town of Lyme and is northwest of Watertown.
The village in July, 1853 contained about fifty dwellings, along with other structures.
In 1874, Chaumont became an incorporated village.
According to the United States Census Bureau, the village has a total area of 1.1 square miles (2.8 km²), of which, 1.0 square miles (2.6 km²) of it is land and 0.1 square miles (0.2 km²) of it (7.27%) is water.
The village is on the south side of the Chaumont River, where it empties into Chaumont Bay, an arm of Lake Ontario. Much of the village is on a peninsula , which ends at Independence Point.
New York State Route 12E passes through the village as Main Street. County Road 179 (Evans Street) enters the village from the northeast.
There were 233 households out of which 30.5% had children under the age of 18 living with them, 47.6% were married couples living together, 11.2% had a female householder with no husband present, and 38.2% were non-families. 33.0% of all households were made up of individuals and 19.7% had someone living alone who was 65 years of age or older. The average household size was 2.48 and the average family size was 3.22.
In the village the population was spread out with 25.0% under the age of 18, 9.8% from 18 to 24, 27.0% from 25 to 44, 22.6% from 45 to 64, and 15.5% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 87.9 males. For every 100 females age 18 and over, there were 80.5 males.
The median income for a household in the village was $37,750, and the median income for a family was $49,107. Males had a median income of $34,375 versus $26,000 for females. The per capita income for the village was $16,608. About 1.6% of families and 8.4% of the population were below the poverty line, including 4.2% of those under age 18 and 9.5% of those age 65 or over.