Educational levels
Data about Long Island from the Census Bureau's 2008-2010 American Community Survey for the county and town level on educational attainment. Some towns are not listed because the number of residents surveyed was too small. Also, because this information is based on surveys, there is a different margin of error for each statistic. A complete listing of those margins and of all the data from Long Island, including information from 45 communities with populations of 20,000 or more, is available on this PDF.
| Location | Population over 25 | Less than grade 9 | HS no diploma | HS diploma | Some college no degree | Associates degree | Bachelors degree | Post grad degree | HS graduate or higher | Bachelors or higher |
| North Hempstead Town | 154,232 | 5.2 | 4.3 | 20.6 | 12.9 | 5.6 | 26.6 | 24.8 | 90.5 | 51.4 |
| East Hampton Town | 16,840 | 2.5 | 5.3 | 22.2 | 18.5 | 5.9 | 23.9 | 21.7 | 92.1 | 45.6 |
| Huntington Town | 139,124 | 3.7 | 4.0 | 21.6 | 14.9 | 8.7 | 25.8 | 21.2 | 92.3 | 47.0 |
| Long Beach City | 25,835 | 4.5 | 3.8 | 24.9 | 15.2 | 7.4 | 24.4 | 19.7 | 91.6 | 44.1 |
| Oyster Bay Town | 203,025 | 2.6 | 3.6 | 25.6 | 16.0 | 8.1 | 24.6 | 19.4 | 93.8 | 44.0 |
| Smithtown Town | 78,687 | 1.7 | 2.4 | 26.3 | 17.7 | 9.5 | 22.9 | 19.4 | 95.9 | 42.3 |
| Nassau County | 908,978 | 5.2 | 5.1 | 25.2 | 15.9 | 7.6 | 22.6 | 18.4 | 89.7 | 41.0 |
| Southampton Town | 41,776 | 5.8 | 5.5 | 23.2 | 16.5 | 7.7 | 23.2 | 18.1 | 88.7 | 41.3 |
| Glen Cove City | 18,512 | 10.4 | 5.5 | 27.0 | 15.8 | 3.0 | 21.4 | 16.8 | 84.0 | 38.2 |
| Riverhead Town | 22,952 | 3.7 | 5.6 | 31.9 | 20.8 | 8.0 | 13.8 | 16.2 | 90.7 | 30.0 |
| Hempstead Town | 507,374 | 6.0 | 6.0 | 26.3 | 16.9 | 8.2 | 20.5 | 16.0 | 88.0 | 36.6 |
| Southold Town | 17,016 | 7.0 | 3.6 | 26.7 | 18.4 | 7.2 | 22.4 | 14.7 | 89.4 | 37.1 |
| Suffolk County | 999,495 | 4.2 | 5.9 | 30.4 | 18.2 | 9.0 | 18.0 | 14.3 | 89.8 | 32.2 |
| Brookhaven Town | 317,700 | 2.7 | 6.3 | 33.1 | 19.0 | 9.3 | 16.0 | 13.6 | 91.0 | 29.6 |
| Islip Town | 220,898 | 6.8 | 7.1 | 32.4 | 18.7 | 9.2 | 14.9 | 10.9 | 86.1 | 25.8 |
| Babylon Town | 142,458 | 5.2 | 7.3 | 35.7 | 19.4 | 9.1 | 14.5 | 8.8 | 87.5 | 23.3 |