County Maps US

Nassau County, Florida

A county in Florida, ranked 37 of 67 by population.

CountyFIPS 12089

Within Florida
Nassau County, highlighted, with the areas around it. Boundaries generalised from the 2025 Census cartographic boundary file; neighbour fills carry no data. The dot marks Fernandina Beach, the county seat, located via the 2025 Census Gazetteer.

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Population
106,879
+15,839 (+17.4%) since 2020
Land area
648.7
square miles. A further 10.6% of the total area is water
Population density
165
people per square mile, computed rather than published
County seat
Fernandina Beach
Seat of county government.
Established
1824
201 years ago
Largest city
Fernandina Beach city
Population 13,869.

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; Wikidata (CC0), Wikidata. Retrieved 30 August 2026.

Satellite view

Aerial imagery of Nassau County with its boundary drawn on top. A map shows you the shape; this shows you what is inside it, and which side of the line a place falls on.

Aerial view of Nassau County, Florida from the USGS National Map, with its boundary outlined
Imagery: USGS National Map, USGS Imagery Only, public domain, requested from USGS by your browser when you reach this point on the page, at 776 by 800 pixels. The boundary is the 2025 Census cartographic boundary file, reprojected to Web Mercator to match the imagery. You can also open the USGS National Map viewer.

Where Nassau County ranks

Position among the 67 counties of Florida, and among all 3,144 US counties and county-equivalents. Computed from the figures on this page.

MeasureValueIn FloridaNationally
Population106,87937th of 67590th of 3,144
Land area648.7 sq mi39th of 671,453rd of 3,144
Population density165 per sq mi36th of 67649th of 3,144
Median household income$89,8044th of 67308th of 3,143

Full data for Nassau County

Every figure below is attributed to the Census Bureau product it came from, with the vintage of that product.
MeasureValueSource and vintage
Population106,879Vintage 2025 Population Estimates
Population in 202091,040Vintage 2025 Population Estimates
2020 estimates base?90,359Vintage 2025 Population Estimates
Land area648.7 sq mi2025 Gazetteer Files
Water area77.2 sq mi2025 Gazetteer Files
Total area725.9 sq mi2025 Gazetteer Files
Population density?165 per sq miComputed: Vintage 2025 estimates divided by 2025 Gazetteer land area
Median household income$89,804American Community Survey 2020-2024 5-Year Estimates
Median home value$382,800American Community Survey 2020-2024 5-Year Estimates
Median age46.5American Community Survey 2020-2024 5-Year Estimates
Households39,307American Community Survey 2020-2024 5-Year Estimates
Housing units45,058American Community Survey 2020-2024 5-Year Estimates

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026. Population density is computed here, not published: it divides the Vintage 2025 population estimate by the 2025 Gazetteer land area, which are two different Census products. Retrieved 30 August 2026.

How the population changed

The Census Bureau publishes the components behind an estimate, not just the total. For the year to July 2025:

Births minus deaths
-148
926 births, 1,074 deaths
Net migration
+2,543
More people moved in than moved out.

Source: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026. Retrieved 30 August 2026.

The 4 areas bordering Nassau County

Ordered by the length of the border actually shared, which the Census Bureau publishes in its county adjacency file and which no other county reference presents.

Bordering areaStateShared borderPopulation
Duval CountyFlorida73 mi1,062,963
Charlton CountyGeorgia62 mi13,121
Camden CountyGeorgia52 mi60,143
Baker CountyFlorida6.1 mi29,737

Source: US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. Retrieved 30 August 2026.

All 67 counties of Florida

Open the interactive Florida county map, or jump straight to any of them.

Data on this page last rebuilt 30 August 2026. How these figures are produced.