Pahoa (Hawaiian: Pāhoa) is a census-designated place (CDP) in the District of Puna in Hawai‘i County, Hawai‘i, United States. The population was 962 at the 2000 census. The population dropped by 1.8% to 945 at the 2010 census.
According to the United States Census Bureau, the CDP has a total area of 2.3 square miles (6.0 km2), all of it land. Soils underlying the Pahoa area are volcanic in origin, deriving from the currently active Kīlauea Volcano. (Earth Metrics Inc., 1986) Kīlauea is one of the Earth's most active volcanoes, with the January 2006 eruption being the longest rift zone eruption in Kīlauea's 200-year recorded history. (Volcanology, 2007) The volcanic soils underlying Pahoa are considered to have been generated by lava flows within the last 125 to 500 years. For example, the eruption of 1840 is known to have deposited a lava flow within 1.5 miles (2.4 km) of Pahoa. Both Hawaii Route 130 and Hawaii Route 132 enter the town boundaries.
As of the census of 2010, there were 945 people in 321 households residing in the CDP. The population density was 410.9 people per square mile (160.2/km²). There were 356 housing units at an average density of 154.8 per square mile (60.3/km²).