Suffolk County Legislative District 5 runs from Stony Brook to Port Jefferson on the North Shore and South to Terryville and Coram.
The district encompasses the unincorporated hamlets of:
- Coram
- East Setauket
- Setauket
- Stony Brook
- South Setauket (including South Setauket Park)
- Port Jefferson
- Port Jefferson Station
- Terryville
The district also includes the incorporated villages of:
- Village of Belle Terre
- Village of Old Field
- Village of Poquott
- Village of Port Jefferson