Suffolk County Population 2018
Suffolk County's estimated population is 1,492,953 with a growth rate of -0.09% in the past year according to the most recent United States census data. Suffolk County is the 4th largest county in New York.
| Year | Population | Growth | Growth Rate |
| 2017 | 1,492,953 | -1,381 | -0.09% |
| 2016 | 1,494,334 | -4,613 | -0.31% |
| 2015 | 1,498,947 | -1,691 | -0.11% |
| 2014 | 1,500,638 | -465 | -0.03% |
| 2013 | 1,501,103 | 1,831 | 0.12% |
| 2012 | 1,499,272 | -802 | -0.05% |
| 2011 | 1,500,074 | 5,385 | 0.36% |
| 2010 | 1,494,689 | 172,825 | 13.07% |
| 1990 | 1,321,864 | 37,633 | 2.93% |
| 1980 | 1,284,231 | 159,281 | 14.16% |
| 1970 | 1,124,950 | 458,166 | 68.71% |
| 1960 | 666,784 | 390,655 | 141.48% |
| 1950 | 276,129 | 78,774 | 39.91% |
| 1940 | 197,355 | 36,300 | 22.54% |
| 1930 | 161,055 | 50,809 | 46.09% |
| 1920 | 110,246 | 14,108 | 14.67% |
| 1910 | 96,138 | 18,556 | 23.92% |
| 1900 | 77,582 | 15,091 | 24.15% |
| 1890 | 62,491 | 8,603 | 15.96% |
| 1880 | 53,888 | 6,964 | 14.84% |
| 1870 | 46,924 | 3,649 | 8.43% |
| 1860 | 43,275 | 6,353 | 17.21% |
| 1850 | 36,922 | 4,453 | 13.71% |
| 1840 | 32,469 | 5,689 | 21.24% |
| 1830 | 26,780 | 2,508 | 10.33% |
| 1820 | 24,272 | 3,159 | 14.96% |
| 1810 | 21,113 | 1,378 | 6.98% |
| 1800 | 19,735 | 3,295 | 20.04% |
| 1790 | 16,440 | 0.00% |