Seaford: Demographics & People
Seaford's population stands at 8,485 people, in 3,516 households. Population grew 2.8% from 8,255 (2022) to 8,485 (2024). Median age 41.1 years. (10.8y younger than Sussex County; 4.1y older than Delaware). Children under 18 are 23% of the population. Population is 49% White (non-Hispanic) and 22% Black. The community is moderately diverse (Simpson index 0.57). 69% of households are family-led. County is gaining 17,165 residents per year (2022-2023). County health: 39% adult obesity, 16% smoke.
- 2.4 people per household (vs Delaware avg 2.5).
- 31% non-family households (singles, roommates) (vs Delaware 41%).
- 72 dependents per 100 working-age (youth + seniors / 18-64) (vs Delaware 70).
Population & Trend
Population grew 2.8% from 8,255 (2022) to 8,485 (2024) — about 4.7× the recent U.S. annual rate of ~0.6%/yr. Estimated 2026 population: ~8,723 (extrapolated at 1.4%/yr trend). Census Bureau Vintage estimate: 9,048.
| Census data vintage | 2024 |
|---|---|
| Population | 237,378 people |
| Annual growth rate · Population change | 2.8% |
| Annual growth rate · Population (2022) | 8,255 |
| Annual growth rate · Population (2024) | 8,485 |
| Annual growth rate · Population growing | Yes |
| Annual growth rate · Trend category | growing |
| Population | 8,485 people (vs Delaware 13,439) |
| Population Estimate | 9,048 |
Sources: Census ACS 5-Year 2023, Table B01003 · Refreshed 2026-04-12
Age Distribution
Median age 41.1y is 2.2 years older than the U.S. median (38.9y). Children under 18 make up 23% — above the U.S. share of ~22%.
| Age Summary · Median age | 41.1 years (vs Delaware 37.0y) |
|---|---|
| Age Summary · Children Pct | 23.2% |
| Age Summary · Character | established |
| Age Summary · Total Pop | 8,485 |
| Age Summary · Under 18 | 1,970 |
| Age Summary · 18 To 34 | 1,721.0× |
| Age Summary · 35 To 64 | 3,216.0× |
| Age Summary · 65 Plus | 1,578 |
| Population under 18 | 1,970 |
| Median age | 41.1 years (vs Delaware 37.0y) |
Sources: Census ACS 5-Year 2024 — place-level B01001 query · Census ACS 5-Year 2023 · Refreshed 2026-04-29
Race, Ethnicity & Diversity
Of 8,485 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.57 (0 = single group, 1 = perfectly even distribution); this is read as moderately diverse.
| White residents | 4,473 |
|---|---|
| Black residents | 2,161 |
| Asian residents | 178 |
| Hispanic or Latino residents | 865 |
| Diversity Index · Diversity index (Simpson) | 56.8% |
| Diversity Index · Diversity label | moderately diverse |
| Diversity Index · Groups counted | 4 |
| Diversity Index · Largest group share | 58.3% |
| Asian population | 1.2% (vs Delaware 2.9%) |
| Black population | 22.4% (vs Delaware 26.7%) |
| Hispanic or Latino population | 12.5% (vs Delaware 10.7%) |
| White (non-Hispanic) population | 49.0% (vs Delaware 51.8%) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Ancestry
Self-reported ancestry from Census ACS — what residents report as their ethnic origin, separate from race. Counts can exceed population because people can list multiple ancestries.
Top (8)
Citizenship & Origin
Where residents were born and their citizenship status (Census ACS).
| Residents born in this state | 3,882 |
|---|---|
| Residents born in another state | 3,737 |
| Share born in this state | 45.8% |
| Share born in another state | 54.2% |
| Total foreign-born residents | 917 |
| From Europe | 21 |
| From Africa | 116 |
Households & Family Composition
3,516 households. Averaging 2.3 people each — smaller than the U.S. average of 2.5. 69% are family households — above the U.S. share of ~65%. Of 2,405 families, 28% are married couples with children.
| Children under 18 | 1,974 |
|---|---|
| Total families | 2,405 |
| Married couples with children | 670 |
| Single-parent households | 120 |
| Average household size | 2.32 |
| Women who gave birth (past year) | 17.5% |
| Grandparents living with grandchildren | 106 |
| Grandparents responsible for grandchildren | 67 |
| Family households | 2,415 households (vs Delaware 3,428) |
| Households that are families | 68.7% (vs Delaware 58.6%) |
| Total households | 3,516 households (vs Delaware 5,560) |
Sources: Census ACS 5-Year 2023 · Refreshed 2026-04-12
Residential Stability & Migration
How long residents have lived here and where they came from. 14.9% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is gaining 17,165 residents per year on net (IRS migration data).
| Moved within the county (past year) | 14.9% |
|---|---|
| Migration · People moving in (annual) | 246,573 |
| Migration · People moving out (annual) | 229,408 |
| Migration · Net migration (in − out) | 17,165 |
| Migration · Population growing | Yes |
| Migration · Year | 2022-2023 |
Sources: IRS SOI Migration 2021-2022 · Refreshed 2026-04-12
Disability
Census ACS measures self-reported functional limitations — vision, hearing, mobility, cognitive, self-care, or independent-living. The U.S. baseline disability rate is about 12–13%; rates trend higher with median age.
| Residents with a disability | 547 |
|---|---|
| Disability rate | 7.0% |
Group Quarters
Group quarters are non-household living arrangements counted by the Census — college dormitories, nursing homes, military barracks, group homes, correctional facilities, and similar institutional or shared housing. 276 residents live in group quarters (3.3% of population).
| Living in group quarters | 276 |
|---|
Other
| Congressional District · Congress | 118th |
|---|---|
| Cdc Birth Rate · Fips | 10005 |
| Cdc Birth Rate · State Fips | 10 |
| Cdc Birth Rate · County Fips | 005 |
| Cdc Birth Rate · County | Sussex |
| Cdc Birth Rate · Birth Rate | 27.6% |
| Cdc Birth Rate · Lower Ci | 25.40 |
| Cdc Birth Rate · Upper Ci | 30.00 |
| Cdc Mortality · Fips | 10005 |
| Cdc Mortality · County | Sussex County |
| Cdc Mortality · Urban Rural | Medium metro |
| Cdc Mortality · Total Deaths 2020 2023 | 9,999 |
| Cdc Vaccination · Fips | 10005 |
| Cdc Vaccination · County | Sussex County |
| Cdc Vaccination · Dose1 Pop Pct | 86.5% |
| Cdc Vaccination · Series Complete Pct | 72.9% |
| Cdc Vaccination · Booster Pct | 55.3% |
| Cdc Vaccination · Population 2019 | 234,225 |
| Cdc Vaccination · Metro Status | Metro |
| Family Score · Score | 7.30 |
| Family Score · Schools | 7 |
| Family Score · Childcare Centers | 6 |
| Family Score · Youth Sports Orgs | 2 |
| Family Score · Children Pct | 23.2% |
| Family Score · Rating | excellent |
| Town Summary · Key Facts | population 8,485, growing, established, middle-class, mixed |
| Town Summary · Population | 8,485 people (vs Delaware 13,439) |
| Town Summary · County | Sussex County |
Sources: NCES school congressional district assignment · federal dataset cascade