Farmer is an unincorporated community in central Farmer Township, Defiance County, Ohio, United States. It has a post office with the ZIP code 43520.USPS – Cities by ZIP Code It is located at the intersection of State Routes 2 and 249.

History Farmer was named for Nathaniel Farmer, an early settler.

Notable Abe L. Biglow, businessman, educator, and member of the Wisconsin State Assembly William P. Richardson, co-founder and first Dean of Brooklyn Law School

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