Millville: Demographics & People

Millville is home to 2,430 people, in 1,291 households. Population grew 18.0% from 2,059 (2022) to 2,430 (2024). Median age 65.1 years. (13.2y older than Sussex County; 28.1y older than Delaware). Children under 18 are 6% of the population. Population is 88% White (non-Hispanic) and 8% Hispanic or Latino. The community is relatively homogeneous (Simpson index 0.08). 63% of households are family-led. County is gaining 17,165 residents per year (2022-2023). County health: 39% adult obesity, 16% smoke.

Population & Trend

Population grew 18.0% from 2,059 (2022) to 2,430 (2024) — about 30.0× the recent U.S. annual rate of ~0.6%/yr. Estimated 2026 population: ~2,887 (extrapolated at 9.0%/yr trend). Census Bureau Vintage estimate: 3,576.

Census data vintage2024
Population237,378 people
Annual growth rate · Population change18.0%
Annual growth rate · Population (2022)2,059
Annual growth rate · Population (2024)2,430
Annual growth rate · Population growingYes
Annual growth rate · Trend categorybooming
Population2,430 people (vs Delaware 13,439) population: 4 observations from 2026-04-17 to 2026-04-28
Population Estimate3,576

Sources: Census ACS 5-Year 2023, Table B01003  ·  Refreshed 2026-04-12

Age Distribution

Median age 65.1y is 26.2 years older than the U.S. median (38.9y). Children under 18 make up 6% — below the U.S. share of ~22%.

Age Summary · Median age65.1 years (vs Delaware 37.0y)
Age Summary · Children Pct6.5%
Age Summary · Characterretirement community
Age Summary · Total Pop2,430
Age Summary · Under 18159
Age Summary · 18 To 34184.0×
Age Summary · 35 To 64852.0×
Age Summary · 65 Plus1,235
Population under 18159
Median age65.1 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 2,430 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.08 (0 = single group, 1 = perfectly even distribution); this is read as relatively homogeneous.

White residents1,907
Black residents27
Asian residents15
Hispanic or Latino residents44
Diversity Index · Diversity index (Simpson)8.4%
Diversity Index · Diversity labelrelatively homogeneous
Diversity Index · Groups counted4
Diversity Index · Largest group share95.7%
Asian population0.7% (vs Delaware 2.9%)
Black population1.3% (vs Delaware 26.7%)
Hispanic or Latino population7.8% (vs Delaware 10.7%)
White (non-Hispanic) population87.7% (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)

(unnamed)
Irish
(unnamed)
German
(unnamed)
Italian
(unnamed)
American
(unnamed)
English
(unnamed)
Polish
(unnamed)
Hispanic Total
(unnamed)
Puerto Rican

Citizenship & Origin

Where residents were born and their citizenship status (Census ACS).

Residents born in this state294
Residents born in another state1,939
Share born in this state12.1%
Share born in another state87.9%
Total foreign-born residents88
From Europe34
From Africa45

Households & Family Composition

1,291 households. Averaging 1.8 people each — smaller than the U.S. average of 2.5. 63% are family households — below the U.S. share of ~65%. Of 686 families, 2% are married couples with children.

Children under 1896
Total families686
Married couples with children16
Single-parent households23
Average household size1.76
Women who gave birth (past year)25.6%
Grandparents living with grandchildren6
Family households809 households (vs Delaware 3,428)
Households that are families62.7% (vs Delaware 58.6%)
Total households1,291 households (vs Delaware 5,560) total_households: 2 observations from 2026-04-23 to 2026-04-23

Sources: Census ACS 5-Year 2023  ·  Refreshed 2026-04-12

Residential Stability & Migration

How long residents have lived here and where they came from. 15.0% 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)15.0%
Migration · People moving in (annual)246,573
Migration · People moving out (annual)229,408
Migration · Net migration (in − out)17,165
Migration · Population growingYes
Migration · Year2022-2023

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 disability133
Disability rate6.5%

Other

Congressional District · Districtat-large
Congressional District · FormattedDE-AL
Congressional District · Congress118th
Cdc Birth Rate · Fips10005
Cdc Birth Rate · State Fips10
Cdc Birth Rate · County Fips005
Cdc Birth Rate · CountySussex
Cdc Birth Rate · Birth Rate27.6%
Cdc Birth Rate · Lower Ci25.40
Cdc Birth Rate · Upper Ci30.00
Cdc Mortality · Fips10005
Cdc Mortality · CountySussex County
Cdc Mortality · Urban RuralMedium metro
Cdc Mortality · Total Deaths 2020 20239,999
Cdc Vaccination · Fips10005
Cdc Vaccination · CountySussex County
Cdc Vaccination · Dose1 Pop Pct86.5%
Cdc Vaccination · Series Complete Pct72.9%
Cdc Vaccination · Booster Pct55.3%
Cdc Vaccination · Population 2019234,225
Cdc Vaccination · Metro StatusMetro
Family Score · Score10
Family Score · Schools20
Family Score · Children Pct6.5%
Family Score · Ratingexcellent
Town Summary · Key Factspopulation 2,430, booming, retirement community, upper-middle, white collar
Town Summary · Population2,430 people (vs Delaware 13,439)
Town Summary · CountySussex County

Sources: Census place-to-CD118 crosswalk (place_fips) · federal dataset cascade