Geography of Trinity County
Small towns and open country define Trinity County. Its 14,384 residents are spread across 693 square miles, giving the county a density typical of rural Texas.
It lies in the East Texas region at about 31.09° N, 95.14° W and is 218th in size among Texas's 254 counties. Trinity County shares boundaries with 5 other Texas counties, and the closest major cities are College Station (about 78 miles away in a straight line) and Tyler (about 88 miles).
East Texas is the state's forested corner — the Piney Woods, red-clay hills, lakes and river bottoms that have more in common with the Deep South than with the open West. Timber, poultry, oil and gas, and growing retirement and lake communities shape its economy.
For a broader view of how Trinity County fits within the state, download our free Texas map with counties and cities PDF — a printable, high-resolution reference showing all 254 Texas counties labeled with their county seats.
Population & demographics
With approximately 14,384 residents across 693 square miles, Trinity County has a population density of about 20.8 people per square mile. Like much of West and South Texas, the county is sparsely populated, with wide-open country between settlements.
County seat: Groveton
County government for Trinity County is based in Groveton. The commissioners court, made up of a county judge and four precinct commissioners, meets here and sets the county budget, roads policy and tax rate. For many residents, a trip to Groveton combines county business with groceries, school events and church.
History & name origin
Trinity County was established in 1850 and was named for The Trinity River, named for the spiritual concept of the Trinity. It was carved from territory previously part of Houston County.
Trinity County, Texas — frequently asked questions
Quick answers about Trinity County geography, population, county seat, neighboring counties, and how to use the maps on this page. Figures are sourced from the U.S. Census Bureau; answers are written and reviewed by the Texas County Map team.
Where is Trinity County, Texas located?+
Trinity County is located in the East Texas region of Texas at approximately 31.089° N, 95.135° W. It is one of the 254 counties of Texas and carries U.S. Census FIPS code 48455. The interactive map on this page renders the official U.S. Census TIGER boundary for Trinity County over real-world OpenStreetMap, Esri satellite, and topographic basemaps.
How big is Trinity County in square miles?+
Trinity County covers approximately 693 square miles of land in the East Texas region — a compact county by Texas standards. By land area it ranks 218th out of 254 Texas counties. The full bounding box of the county is rendered to scale on the interactive map and matches the U.S. Census TIGER 2023 polygon.
What is the population of Trinity County, Texas?+
Trinity County has a population of approximately 14,384 residents. With 693 square miles of land, that works out to a population density of about 20.8 people per square mile, which is rural for a Texas county. That makes Trinity County the 143rd most populous of the 254 counties in Texas.
What is the county seat of Trinity County?+
Groveton is the county seat of Trinity County, Texas, which was organized in 1850 and named for The Trinity River, named for the spiritual concept of the Trinity. Trinity County was originally carved out of Houston County. County government offices, courthouses, and most public records for Trinity County are located in Groveton.
Which Texas counties border Trinity County?+
Trinity County shares borders with Houston, Polk, San Jacinto, Angelina, and Walker counties. These 5 neighboring counties are highlighted on the schematic boundary map and linked at the bottom of this page so you can quickly compare population, area, and county seats across the East Texas region.
Where can I download or print a map of Trinity County?+
Use the "Download PDF" button below the Trinity County map on this page to save a letter-size PDF of the county boundary, neighboring counties and incorporated places, drawn from U.S. Census Bureau 2023 boundary files. The "Official TxDOT road map" button downloads the Texas Department of Transportation county road mapbook for Trinity County. Both files are stored on this site and download directly. Our free Texas map with counties and cities PDF shows all 254 counties on one sheet.
What is the FIPS code for Trinity County, Texas?+
The full 5-digit U.S. Census FIPS code for Trinity County is 48455, made up of Texas state code 48 and the 3-digit county code 455. This is the same FIPS code used by the U.S. Census Bureau TIGER/Line files, the American Community Survey, and most federal datasets that key on county.