Fairfield Township may refer to:

Illinois Fairfield Township, Bureau County, Illinois

Indiana Fairfield Township, DeKalb County, Indiana Fairfield Township, Franklin County, Indiana Fairfield Township, Tippecanoe County, Indiana

Iowa Fairfield Township, Buena Vista County, Iowa Fairfield Township, Cedar County, Iowa Fairfield Township, Fayette County, Iowa Fairfield Township, Grundy County, Iowa Fairfield Township, Jackson County, Iowa Fairfield Township, Palo Alto County, Iowa

Kansas Fairfield Township, Russell County, Kansas

Michigan Fairfield Township, Lenawee County, Michigan Fairfield Township, Shiawassee County, Michigan

Minnesota Fairfield Township, Crow Wing County, Minnesota Fairfield Township, Swift County, Minnesota

Missouri Fairfield Township, Carroll County, Missouri

Nebraska Fairfield Township, Clay County, Nebraska Fairfield Township, Harlan County, Nebraska

New Jersey Fairfield Township, Cumberland County, New Jersey Fairfield Township, Essex County, New Jersey

North Carolina Fairfield Township, Hyde County, North Carolina, in Hyde County, North Carolina

North Dakota Fairfield Township, Grand Forks County, North Dakota, in Grand Forks County, North Dakota

Ohio Fairfield Township, Butler County, Ohio Fairfield Township, Columbiana County, Ohio Fairfield Township, Highland County, Ohio Fairfield Township, Huron County, Ohio Fairfield Township, Madison County, Ohio Fairfield Township, Tuscarawas County, Ohio Fairfield Township, Washington County, Ohio

Pennsylvania Fairfield Township, Crawford County, Pennsylvania Fairfield Township, Lycoming County, Pennsylvania Fairfield Township, Westmoreland County, Pennsylvania

South Dakota Fairfield Township, Beadle County, South Dakota, in Beadle County, South Dakota