Colgate is an unincorporated community in Washington County, Wisconsin, United States, straddling the county line with Waukesha County. Colgate is located partially in the village of Richfield, and the town of Lisbon. Its ZIP code is 53017.The Fox River, an Illinois River tributary, rises in a small, unnamed swamp, 1 mi southeast of the community of Colgate. The Bark River also originates to the north and runs in a southwesterly direction.