Geography of Trinity County
Trinity County sits at roughly 31.09° N and 95.14° W in the East Texas region of Texas, spanning 693 square miles of terrain that includes the landscape characteristic of the area — from open ranchland and farmland to small-town main streets. The county's centroid is near Groveton, and the county shares boundaries with 5 neighboring counties.
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
Groveton serves as the seat of government for Trinity County. The county courthouse, commissioners court, district clerk, and primary public records are located here. As with all 254 Texas counties, the county seat is the anchor of civic life and the principal address for elections, permits, and court filings.
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. Every answer is generated from the official U.S. Census data backing this site.
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?+
A free, print-ready PDF map of Trinity County is available from the "Download PDF" button at the top of this page. The printable layout uses authentic U.S. Census TIGER boundary geometry for Trinity County, includes a Texas locator inset, and is sized for standard 8.5" × 11" Letter paper. For interactive use, the live Leaflet map on this page supports OpenStreetMap, Esri satellite, Esri topographic, and Carto light basemaps with zoom, scale bar, and fullscreen.
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.