Granby is a town located in the southwest corner of Oswego County. The town borders the Oswego River and the City of Fulton to the east, Onondaga County to the south, the town of Hannibal on the west, and towns of Oswego and Minetto on the north. The zip codes for Granby are 13069, 13074, and 13033. The school districts for this area include Fulton City School District, Phoenix Central School District, and Hannibal Central School District.
As of the 2020 Census, there were 6,520 people (a change of -4.4% since 2010) residing in the town of Granby. The share of the total population consists of 78.5% adults age 18 or older and 21.5% youths under the age of 18. A change of -0.5% and -16.4% respectively.
There was an 8.6% vacancy rate in 2020 in the town of Granby. There were 2,798 total housing units, a -0.1% change since 2010. Of the 2,798, 2,558 housing units were occupied and 240 were vacant.