Guilford is a census-designated place (CDP) in Franklin County, Pennsylvania, United States.

According to the United States Census Bureau, the CDP has a total area of 1.3 square miles (3.4 km2), all land.

There were 751 housing units at an average density of 600.4 per square mile (231.8/km2).

16.0% of all households were made up of individuals, and 9.7% had someone living alone who was 65 years of age or older.

None of the families and 2.0% of the population were living below the poverty line, including no under eighteens and 7.3% of those over 64.