Language Spoken At Home in Southold
*Base on 2012 Data
| Population 5 years and over | 5,656 | 100% |
| English only | 5,258 | 93.0% |
| Language other than English | 398 | 7.0% |
| Speak English less than very well | 193 | 3.4% |
| Spanish | 114 | 2.0% |
| Speak English less than very well | 62 | 1.1% |
| Other Indo-European languages | 168 | 3.0% |
| Speak English less than very well | 40 | 0.7% |
| Asian and Pacific Islander languages | 116 | 2.1% |
| Speak English less than very well | 91 | 1.6% |
| Other languages | 0 | 0.0% |
| Speak English less than very well | 0 | 0.0% |
Ancestry in Southold
*Base on 2012 Data
| Total population | 5,965 | 100% |
| American | 64 | 1.1% |
| Arab | 0 | 0.0% |
| Czech | 68 | 1.1% |
| Danish | 0 | 0.0% |
| Dutch | 88 | 1.5% |
| English | 774 | 13.0% |
| French (except Basque) | 131 | 2.2% |
| French Canadian | 158 | 2.6% |
| German | 1,671 | 28.0% |
| Greek | 71 | 1.2% |
| Hungarian | 88 | 1.5% |
| Irish | 1,818 | 30.5% |
| Italian | 1,314 | 22.0% |
| Lithuanian | 16 | 0.3% |
| Norwegian | 92 | 1.5% |
| Polish | 730 | 12.2% |
| Portuguese | 0 | 0.0% |
| Russian | 140 | 2.3% |
| Scotch-Irish | 48 | 0.8% |
| Scottish | 127 | 2.1% |
| Slovak | 12 | 0.2% |
| Subsaharan African | 0 | 0.0% |
| Swedish | 194 | 3.3% |
| Swiss | 47 | 0.8% |
| Ukrainian | 38 | 0.6% |
| Welsh | 113 | 1.9% |
| West Indian (excluding Hispanic origin groups) | 0 | 0.0% |
Households By Type in Southold
*Base on 2012 Data
| Total households | 2,446 | 100% |
| Family households (families) | 1,837 | 75.1% |
| With own children under 18 years | 607 | 24.8% |
| Married-couple family | 1,637 | 66.9% |
| With own children under 18 years | 537 | 22.0% |
| Male householder, no wife present, family | 0 | 0.0% |
| With own children under 18 years | 0 | 0.0% |
| Female householder, no husband present, family | 200 | 8.2% |
| With own children under 18 years | 70 | 2.9% |
| Nonfamily households | 609 | 24.9% |
| Householder living alone | 482 | 19.7% |
| 65 years and over | 296 | 12.1% |
| Households with one or more people under 18 years | 679 | 27.8% |
| Households with one or more people 65 years and over | 1,096 | 44.8% |
| Average household size | 2 | 0% |
| Average family size | 3 | 0% |
Relationship in Southold
*Base on 2012 Data
| Population in households | 5,934 | 100% |
| Householder | 2,446 | 41.2% |
| Spouse | 1,621 | 27.3% |
| Child | 1,388 | 23.4% |
| Other relatives | 239 | 4.0% |
| Nonrelatives | 240 | 4.0% |
| Unmarried partner | 136 | 2.3% |
Marital Status in Southold
*Base on 2012 Data
| Males 15 years and over | 2,404 | 100% |
| Never married | 393 | 16.3% |
| Now married, except separated | 1,780 | 74.0% |
| Separated | 16 | 0.7% |
| Widowed | 28 | 1.2% |
| Divorced | 187 | 7.8% |
| Females 15 years and over | 2,635 | 100% |
| Never married | 368 | 14.0% |
| Now married, except separated | 1,749 | 66.4% |
| Separated | 42 | 1.6% |
| Widowed | 315 | 12.0% |
| Divorced | 161 | 6.1% |
Fertility in Southold
*Base on 2012 Data
| Number of women 15 to 50 years old who had a birth in the past 12 months | 73 | 100% |
| Unmarried women (widowed, divorced, and never married) | 0 | 0.0% |
| Per 1,000 unmarried women | 0 | 0% |
| Per 1,000 women 15 to 50 years old | 80 | 0% |
| Per 1,000 women 15 to 19 years old | 0 | 0% |
| Per 1,000 women 20 to 34 years old | 361 | 0% |
| Per 1,000 women 35 to 50 years old | 0 | 0% |
Grandparents in Southold
*Base on 2012 Data
| Number of grandparents living with own grandchildren under 18 years | 31 | 100% |
| Responsible for grandchildren | 7 | 22.6% |
| Less than 1 year | 0 | 0.0% |
| 1 or 2 years | 0 | 0.0% |
| 3 or 4 years | 7 | 22.6% |
| 5 or more years | 0 | 0.0% |
| Number of grandparents responsible for own grandchildren under 18 years | 7 | 100% |
| Who are female | 0 | 0.0% |
| Who are married | 7 | 100.0% |
School Enrollment in Southold
*Base on 2012 Data
| Population 3 years and over enrolled in school | 1,104 | 100% |
| Nursery school, preschool | 136 | 12.3% |
| Kindergarten | 29 | 2.6% |
| Elementary school (grades 1-8) | 507 | 45.9% |
| High school (grades 9-12) | 282 | 25.5% |
| College or graduate school | 150 | 13.6% |
Educational Attainment in Southold
*Base on 2012 Data
| Population 25 years and over | 4,542 | 100% |
| Less than 9th grade | 88 | 1.9% |
| 9th to 12th grade, no diploma | 64 | 1.4% |
| High school graduate (includes equivalency) | 1,208 | 26.6% |
| Some college, no degree | 874 | 19.2% |
| Associate's degree | 501 | 11.0% |
| Bachelor's degree | 979 | 21.6% |
| Graduate or professional degree | 828 | 18.2% |
| Percent high school graduate or higher | 0 | 96.7% |
| Percent bachelor's degree or higher | 0 | 39.8% |
Veteran Status in Southold
*Base on 2012 Data
| Civilian population 18 years and over | 4,801 | 100% |
| Civilian veterans | 628 | 13.1% |
Disability Status Of The Civilian Noninstitutionalized Population in Southold
*Base on 2012 Data
| Total Civilian Noninstitutionalized Population | 5,965 | 100% |
| With a disability | 543 | 9.1% |
| Under 18 years | 1,164 | 100% |
| With a disability | 20 | 1.7% |
| 18 to 64 years | 3,140 | 100% |
| With a disability | 179 | 5.7% |
| 65 years and over | 1,661 | 100% |
| With a disability | 344 | 20.7% |
Residence 1 Year Ago in Southold
*Base on 2012 Data
| Population 1 year and over | 5,905 | 100% |
| Same house | 5,680 | 96.2% |
| Different house in the U.S. | 225 | 3.8% |
| Same county | 190 | 3.2% |
| Different county | 35 | 0.6% |
| Same state | 35 | 0.6% |
| Different state | 0 | 0.0% |
| Abroad | 0 | 0.0% |
Place Of Birth in Southold
*Base on 2012 Data
| Total population | 5,965 | 100% |
| Native | 5,639 | 94.5% |
| Born in United States | 5,488 | 92.0% |
| State of residence | 4,485 | 75.2% |
| Different state | 1,003 | 16.8% |
| Born in Puerto Rico, U.S. Island areas, or born abroad to American parent(s) | 151 | 2.5% |
| Foreign born | 326 | 5.5% |
U.S. Citizenship Status in Southold
*Base on 2012 Data
| Foreign-born population | 326 | 100% |
| Naturalized U.S. citizen | 184 | 56.4% |
| Not a U.S. citizen | 142 | 43.6% |
Year of Entry in Southold
*Base on 2012 Data
| Population born outside the United States | 477 | 100% |
| Native | 151 | 100% |
| Entered 2010 or later | 0 | 0.0% |
| Entered before 2010 | 151 | 100.0% |
| Foreign born | 326 | 100% |
| Entered 2010 or later | 0 | 0.0% |
| Entered before 2010 | 326 | 100.0% |
World Region Of Birth Of Foreign Born in Southold
*Base on 2012 Data
| Foreign-born population, excluding population born at sea | 326 | 100% |
| Europe | 134 | 41.1% |
| Asia | 116 | 35.6% |
| Africa | 0 | 0.0% |
| Oceania | 0 | 0.0% |
| Latin America | 35 | 10.7% |
| Northern America | 41 | 12.6% |