St. Augustine South: Demographics & People

St. Augustine South is home to 4,714 people, in 2,113 households. Population shrank 3.1% from 4,864 (2022) to 4,714 (2024). Median age 50.4 years. (6.2y older than St. Johns County; 7.8y older than Florida). Children under 18 are 13% of the population. Population is 86% White (non-Hispanic) and 8% Hispanic or Latino. The community is somewhat diverse (Simpson index 0.21). 69% of households are family-led. County is gaining 33,939 residents per year (2022-2023). County health: 26% adult obesity, 9% smoke.

Population & Trend

Population shrank 3.1% from 4,864 (2022) to 4,714 (2024). Estimated 2026 population: ~4,569 (extrapolated at -1.5%/yr trend). Census Bureau Vintage estimate: 4,382.

Census data vintage2024
Population273,425 people
Annual growth rate · Population change-3.1%
Annual growth rate · Population (2022)4,864
Annual growth rate · Population (2024)4,714
Annual growth rate · Trend categorydeclining
Population4,714 people (vs Florida 58,838)
Population Estimate4,382

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

Age Distribution

Median age 50.4y is 11.5 years older than the U.S. median (38.9y). Children under 18 make up 13% — below the U.S. share of ~22%.

Age Summary · Median age50.4 years (vs Florida 40.9y)
Age Summary · Children Pct13.3%
Age Summary · Characterretirement community
Population under 18627
Median age50.4 years (vs Florida 40.9y)

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

Race, Ethnicity & Diversity

Of 4,714 residents, race / ethnicity breaks down by Census ACS counts (a person can identify with one or more groups). The Simpson diversity index is 0.21 (0 = single group, 1 = perfectly even distribution); this is read as somewhat diverse.

White residents4,298
Black residents66
Asian residents249
Hispanic or Latino residents248
Diversity Index · Diversity index (Simpson)21.3%
Diversity Index · Diversity labelsomewhat diverse
Diversity Index · Groups counted4
Diversity Index · Largest group share88.4%
Asian population5.1% (vs Florida 2.5%)
Black population0.2% (vs Florida 13.0%)
Hispanic or Latino population7.6% (vs Florida 23.4%)
White (non-Hispanic) population85.7% (vs Florida 46.8%)

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)
English
(unnamed)
Hispanic Total
(unnamed)
Asian
(unnamed)
American
(unnamed)
Polish

Citizenship & Origin

Where residents were born and their citizenship status (Census ACS). 4.4% are foreign-born — below the U.S. average of 13.9%. 2% have naturalized to U.S. citizenship.

Residents born in this state2,170
Residents born in another state2,222
Share born in this state46.0%
Share born in another state54.0%
Native-born U.S. citizens47.1%
Foreign-born residents4.4%
Naturalized citizens2.4%
Total foreign-born residents136
From Europe21
From Africa77

Households & Family Composition

2,113 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 1,401 families, 13% are married couples with children.

Children under 18746
Total families1,401
Married couples with children186
Single-parent households102
Average household size2.29
Women who gave birth (past year)22.3%
Grandparents living with grandchildren82
Grandparents responsible for grandchildren44
Family households1,458 households (vs Florida 15,074)
Households that are families69.0% (vs Florida 64.6%)
Total households2,113 households (vs Florida 22,144)

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

Residential Stability & Migration

How long residents have lived here and where they came from. 8.4% moved within the county in the past year — the U.S. baseline is roughly 8–10%. The surrounding county is gaining 33,939 residents per year on net (IRS migration data).

Moved within the county (past year)8.4%
Migration · People moving in (annual)334,131
Migration · People moving out (annual)300,192
Migration · Net migration (in − out)33,939
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 disability379
Disability rate7.5%

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. 33 residents live in group quarters (0.7% of population).

Living in group quarters33

Other

Congressional District · District6
Congressional District · FormattedFL-06
Congressional District · Congress118th
Cdc Birth Rate · Fips12,109
Cdc Birth Rate · State Fips12
Cdc Birth Rate · County Fips109
Cdc Birth Rate · CountySt Johns
Cdc Birth Rate · Birth Rate6.7%
Cdc Birth Rate · Lower Ci5.80
Cdc Birth Rate · Upper Ci7.60
Cdc Mortality · Fips12,109
Cdc Mortality · CountySt. Johns County
Cdc Mortality · Urban RuralLarge fringe metro
Cdc Mortality · Total Deaths 2020 20236,791
Cdc Vaccination · Fips12,109
Cdc Vaccination · CountySt. Johns County
Cdc Vaccination · Dose1 Pop Pct81.2%
Cdc Vaccination · Series Complete Pct72.8%
Cdc Vaccination · Booster Pct50.2%
Cdc Vaccination · Population 2019264,672
Cdc Vaccination · Metro StatusMetro
Family Score · Score3.50
Family Score · Schools5
Family Score · Children Pct13.3%
Family Score · Ratingfair
Town Summary · Key Factspopulation 4,714, declining, retirement community, upper-middle, mixed
Town Summary · Population4,714 people (vs Florida 58,838)
Town Summary · CountySt. Johns County

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