The Eighth Suffolk County Legislative District is located in the south central part of Suffolk County and almost entirely within the Town of Islip, with a small part located within Brookhaven Town. It includes Bayport-Blue-Point, Holbrook, Holtsville, Sayville, West Sayville, Oakdale and parts of Ronkonkoma, Bohemia and Medford.
The district boundaries are the Islip-Brookhaven town line to the east and the Great South Bay to the south. The western boundary is a jagged line that runs from the western border of Oakdale through the communities of Bohemia and into Ronkonkoma. The northern boundary is located just south of the Long Island Railroad with the exception of small portion to the north of the LIE.
The district consists of 51 election districts with 48,000 registered voters.