Jefferson County is in southeastern Texas near Louisiana and the Gulf Coast. Beaumont is its county seat, and Port Arthur is another major city within the county.
Jefferson County facts
County estimates: American Community Survey (ACS) 2020–2024 5-year release. Boundary and land area: U.S. Census Bureau TIGERweb. Data may change as sources are updated.
Interactive Jefferson County map
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Map tiles © OpenStreetMap contributors. Map boundaries are not legal property lines. Scroll-wheel zoom is disabled to make page scrolling easier.
Where is Jefferson County?
Jefferson County is in southeastern Texas near Louisiana and the Gulf Coast. Beaumont is its county seat, and Port Arthur is another major city within the county.
Its geography includes urban areas, waterways, port-related development, and wetlands. Understanding the county outline and land area helps put these varied places into geographic context.
Jefferson County FIPS code explained
The official county FIPS code is 48245. The first two digits, 48, represent Texas. The final three digits, 245, identify Jefferson County within Texas. Always keep all five digits, including leading zeros if present, when using government datasets or county lookup tools.
Population, income, housing, and land area
Population, household income, median home value, median age, and poverty figures in this profile use the American Community Survey (ACS) 2020–2024 5-year estimates. These are statistical estimates, not live counts or today’s real-estate prices. Household income and owner-occupied home values use the dollar basis of that ACS release.
The county polygon and land area are retrieved from the U.S. Census Bureau’s 2026 TIGERweb geographic service. Population density is calculated using the ACS population estimate divided by the Census boundary’s land area in square miles. Different reference years and statistical uncertainty can affect comparisons.
Compare Jefferson County with other Texas counties
Harris County and Montgomery County offer Southeast Texas comparisons with different population sizes and metro-area characteristics. You can open Harris County and Montgomery County or choose any counties with the County Comparison Tool.
Frequently asked questions
What is the county seat of Jefferson County?
The county seat is Beaumont. That is the county government’s administrative center. The county’s boundary includes additional communities beyond the county seat.
How can I verify Jefferson County’s FIPS code?
Look up 48245 in our FIPS lookup tool or check the U.S. Census Bureau geographic reference information. The code refers to a county, not to a particular ZIP Code or city.
Can I use the map to decide a property line or legal boundary?
No. The map is intended for geographic orientation. Consult an official cadastral survey, local government, or relevant agency for legal property boundaries, tax jurisdictions, emergency services, or election districts.
Why does a number sometimes display as unavailable?
These charts depend on external Census-related services, so individual numbers or boundaries can occasionally be unavailable. Review the Data and Methodology page for the underlying release and limitations.
More useful tools
Return to the Texas county list and map, find counties from ZIP Codes, or use our current county finder.