Mastic Beach is a hamlet and census-designated place, and former village in the southeastern part of the Town of Brookhaven in Suffolk County, on Long Island, in New York, United States.

At $549,500 annually, the village would take up building code enforcement, leaving police, fire, and sanitation to Brookhaven.

The boundaries of the village of Mastic Beach differed from those of the previous census-designated place (CDP).

[7] Residents voted 1,922 to 1,215 on November 8, 2016, to revert to an unincorporated area with services handled by the Town of Brookhaven.

[8][9] The decision to dissolve the village was decided upon due to political issues and fiscal concerns.

[10] A formal dissolution plan was developed over several months and approved by the Village Board (4–1) at a special meeting on March 16, 2017.

[12] Nearby are Smith Point County Park and the Fire Island National Seashore.