Two things happened to the Texas political map between the 2024 general election and the 2026 primary. The Legislature redrew the congressional map in a mid-decade special session. And counties across the state redrew their voting precincts — Tarrant eliminated 137, Dallas cut 94, Harris added 52.
Those two changes get discussed as though they were one event. They were not, and they can be separated exactly — because of something the Legislature did not do.
When the congressional map was redrawn, the State House, State Senate and State Board of Education maps were left untouched. Those three plans are identical in 2026 to their 2024 versions.
That gives us a control group. If redrawing precincts moves voters between districts, it would move them between those districts too — the lines sat still, so anything crossing them is caused by the precincts alone. Measure that, and you have the size of the re-precincting effect with nothing else mixed in.
In this article
- The control says re-precincting moved essentially no one
- Explore your county (interactive statewide map)
- Forty-two counties changed district in their entirety
- Which number you use changes the story
- Your precinct didn’t move. Your congressman did.
- What this does not tell you
- Common questions
- About this analysis
- Sources and method
The control says re-precincting moved essentially no one
Across all 254 Texas counties, comparing every square metre of the state before and after:
| District type | Map status | Territory that changed district |
|---|---|---|
| Congressional | redrawn | 121,370 km² — 17.45% of Texas |
| State House | unchanged | 3.7 km² — 0.00% |
| State Senate | unchanged | 1.6 km² — 0.00% |
| State Board of Education | unchanged | 6.6 km² — 0.00% |
Redrawing every precinct in Texas moved 3.7 square kilometres across a State House line — five one-thousandths of one percent of the state, the sort of number produced by a boundary nudged a few metres down a road.
Redrawing the congressional map moved 121,370 square kilometres.
The ratio is roughly 33,000 to 1. Whatever counties did to their precincts, it is not what changed anyone's representation. The congressional redraw is the entire story.
Explore your county
Every Texas county, shaded by how much of it changed congressional district. Switch between the two units — they disagree, and the disagreement is informative. Counties outlined in black changed entirely.
Hover or tap any county for both
numbers and the raw counts. Data: WattsLab precinct API
(Precincts24G vs Precincts26P).
Forty-two counties changed district in their entirety
73 of Texas's 254 counties saw any congressional change at all. The striking part is how it split:
- 42 counties moved wholesale — 100% of their territory went from one district to another. 89,725 km².
- 31 counties were carved, with only part of their area reassigned. 31,645 km².
The counties that moved in full are, almost without exception, rural:
Matagorda, La Salle, Dimmit, Houston, Liberty, Polk, Wharton, Leon, Live Oak, Anderson, Gonzales, Cherokee, Bosque, Hill, Nacogdoches, Colorado, Lavaca, Fayette, DeWitt, Bee, Angelina, Goliad, Wilson, Hopkins, Karnes, Mills, Guadalupe, Trinity, Lampasas, Wood, Austin, San Jacinto, Washington, Upshur, Waller, Titus, Franklin, Delta, Rains, Morris, Camp, Rockwall
If you live in one of those counties, your county did not change — your congressional district did, and it did so for every acre at once.
The carved counties are where the population is. Two numbers are given for each, because they answer different questions and they do not agree:
| County | By territory | By precinct count |
|---|---|---|
| Brazoria | 99.0% | 95.2% (80/84) |
| San Patricio | 94.8% | 74.1% (20/27) |
| Nueces | 71.0% | 73.5% (97/132) |
| Travis | 63.2% | 51.9% (160/308) |
| Bexar | 57.3% | 54.1% (436/806) |
| Harris | 49.6% | 50.4% (617/1,224) |
| Bell | 42.8% | 52.8% (38/72) |
| Hays | 40.3% | 73.9% (65/88) |
| Hidalgo | 40.1% | 72.5% (187/258) |
| Tarrant | 33.6% | 42.3% (299/707) |
| Dallas | 29.7% | 43.1% (341/791) |
| Fort Bend | 12.2% | 33.3% (67/201) |
| Williamson | 10.2% | 40.1% (71/177) |
| Collin | 9.4% | 24.2% (66/273) |
| El Paso | 7.1% | 9.7% (23/236) |
This is the pattern a redraw leaves: it sweeps whole small counties into a neighboring district, and it slices through the big ones.
Which number you use changes the story
Look at Hays County. 40% of its land changed congressional district — but 74% of its precincts did. Williamson: 10% of the land, 40% of the precincts. Hidalgo: 40% and 73%.
The gap means the redraw cut through the dense parts of those counties and left the empty parts alone. Precincts are drawn to hold roughly comparable numbers of voters, so a precinct is a far better proxy for people than a square kilometre is. Where the precinct share runs far ahead of the territory share, many more voters were moved than the map's shading suggests.
It does not always run that way. In Travis County the relationship inverts — 63% of the territory but 52% of the precincts — meaning the reassigned ground there was the sparser part of the county. San Patricio inverts too, 95% against 74%.
So neither number alone is sufficient, and the direction of the gap is itself the finding: it tells you whether a redraw took a county's dense core or its open ground.
Your precinct didn't move. Your congressman did.
The two changes barely overlap, and the gap is the point. Both columns below are counts of precincts, so they are directly comparable:
| County | Precincts geometrically unchanged | Precincts that changed congressional district |
|---|---|---|
| Harris | 97.4% (1,192/1,224) | 50.4% (617/1,224) |
| Tarrant | 90.7% (641/707) | 42.3% (299/707) |
| Dallas | 81.3% (643/791) | 43.1% (341/791) |
In Harris County, 97 of every 100 precincts are the same shape they were in 2024 — same boundaries, same polling place, same neighbors. Half of them are in a different congressional district.
One concrete case, Tarrant precinct 4391005: its boundary is identical to its 2024 self, not adjusted by a single metre. In 2024 it was in Congressional District 33. It is now in District 12.
Each of those three counties has its own analysis, precinct by precinct, with an interactive map: Harris, Tarrant — the only one of the three where a congressional district left the county outright — and Dallas.
Nothing a voter can see from their doorstep changed. Their representation did.
You can check this county by county: the Harris and Dallas district maps show it precinct by precinct, and the matching precinct explorers show whether the boundaries themselves moved.
What this does not tell you
This measures land and precinct counts, not people. 17.45% of Texas territory changed congressional district. That is not 17.45% of Texans. Rural acreage is not population, and the 42 whole counties that moved contain far fewer people than the slices taken out of Harris and Bexar.
And the error does not run in a reassuring direction. Because precincts are sized to hold roughly comparable numbers of voters, the precinct-count column is the better guide — and in Hays, Hidalgo, Williamson and Fort Bend it is two to four times the territory figure. In those counties the headline area number understates the human effect substantially.
This says nothing about partisan effect. We measured boundaries. There are no election results and no party registration anywhere in this analysis, so it cannot say who benefits, and does not try to. Where territory moved is a matter of public record; what it means politically is a separate question requiring separate data.
Common questions
How many Texas counties changed congressional district in 2026?
73 of Texas's 254 counties saw some congressional change. 42 of those changed entirely, with 100% of their territory moving from one district to another.
How much of Texas changed congressional district?
121,370 km² — 17.45% of the state's area — moved to a different congressional district between the 2024 general election and the 2026 primary.
Did redrawing voting precincts change anyone's congressional district?
Almost no one's. Because the State House, Senate and SBOE maps were left unchanged in 2025, the effect of re-precincting can be measured on its own: statewide it moved 3.7 km² across a State House line, against 121,370 km² moved by the congressional redraw — a ratio of roughly 33,000 to 1.
Why do the land and precinct percentages differ for my county?
Because the precincts that changed district are not average-sized. Where the precinct share exceeds the territory share, the redraw cut through denser ground and moved more voters than the land figure implies. Where it is lower, the reassigned ground was sparser. Precincts hold roughly comparable numbers of voters, so the precinct figure is the better guide to people.
Does this analysis show which party benefits?
No. It uses boundary data only, with no election results and no party registration, so it shows where territory moved but not what that means politically.
About this analysis
Analysis by Watts Lab. Watts Lab compared every square metre of Texas before and after the 2025 congressional redraw — 9,657 precincts against 9,614, across all 254 counties — using the Texas Legislative Council's published boundary files and its own precinct-to-district crosswalks. Both vintages reconcile completely: every precinct in both years is accounted for. The interactive maps on this site are served from a live API built for the purpose.
Every figure above can be recomputed from public data. If you would like the method walked through, a comparable analysis for another state or jurisdiction, or a map built for a question you are trying to answer, get in touch.
Sources and method
Precinct boundaries: Texas Legislative Council, Precincts24G (9,657
precincts, 2024 general) and Precincts26P (9,614 precincts, published 15
July 2026). District assignments: TLC's own authoritative precinct-to-district
crosswalks published alongside each precinct file — no district assignment here is
inferred. Congressional plans PlanC2193 (2021) and PlanC2333
(2025 redraw); PlanH2316, PlanS2168 and PlanE2106
are unchanged between the two vintages, which is what makes the control possible.
Precinct numbers were renumbered between the two years, so precincts are never matched by number. Every piece of ground is intersected between the old and new precinct maps, each piece carries its own before-and-after district, and area is summed into a transfer matrix. Areas are computed in an equal-area projection (EPSG:3083). Both vintages reconcile completely — all 9,657 old and all 9,614 new precincts are accounted for.
A precinct is counted as having changed district when the district holding the largest share of the ground it inherited differs from its own. Precincts assembled from predecessors in two different districts have no single “before”; these are flagged rather than assigned.
The 42 whole-county reassignments were verified by a second, independent route using no geometry at all: for each of those counties, the set of congressional districts covering it in 2024 and the set covering it in 2026 share no members, which can only be true if every part of it changed district.
See something that looks wrong? Tell us
This is a genuinely complicated piece of work — two statewide precinct maps, two congressional plans, and every county in Texas. The people who know a place are usually the first to spot something the data got wrong. If a county looks off, if a number does not match what you know on the ground, or if you would simply like something here explained, please drop us a line. We read every one, and corrections are welcome.