Pfäffikon has an area of . Of this area, 43.3% is used for agricultural purposes, while 23.4% is forested. Of the rest of the land, 16.7% is settled (buildings or roads) and the remainder (16.5%) is non-productive (rivers, glaciers or mountains). housing and buildings made up 11.9% of the total area, while transportation infrastructure made up the rest (4.8%). Of the total unproductive area, water (streams and lakes) made up 11.4% of the area. 13.6% of the total municipal area was undergoing some type of construction.