Texas Electricity Delivery Territory Map

What this dataset represents

Texas's competitive electricity market is served by five major transmission and distribution utilities, or TDUs.

Their service areas do not follow county or city boundaries, and large portions of Texas are served instead by municipal utilities or electric cooperatives where retail electricity choice is not available.

Fixed Rate Electric Plans needed a geographic layer that preserved those distinctions, including municipal and cooperative areas located inside larger TDU territories.

The downloadable dataset on this page is a digitized and reprojected version of the PUCT map titled "Transmission & Distribution Utilities in Competitive Retail Areas", published 25 September 2009.

The same geometry is used by the map on this site.

Why the source is from 2009

The PUCT currently maintains an Electric Service Area Boundaries Viewer that includes investor-owned, municipal and cooperative utilities.

The downloadable files on this page are not built from those layers.

The electric-layer metadata describes the boundaries as unofficial, identifies Platts as the original source for the layer, and contains a use-limitation field referring to a Master Service Agreement with Platts. The feature-level metadata also shows that many boundaries have since been updated from utility-submitted information.

We are not interpreting those restrictions, and nothing here is a conclusion about who owns the data. We simply chose not to redistribute that layer. The files here are derived instead from the PUCT map that is openly published as a PDF, which as of 21 August 2026 is still the map linked from the commission's own electric maps page. That choice comes with an important limitation: the source map is from 2009 and should not be treated as a current picture of Texas service territories.

The two sources also cover different things. The viewer's investor-owned layer carries eight utilities, including El Paso Electric and Entergy Texas, which are investor-owned but not part of the competitive retail market. This dataset carries the five delivery utilities in competitive retail areas, which is the distinction that decides whether a household can shop for a plan.

Public Utility Commission of Texas — Electric Service Area Boundaries Viewer

Source

The PUCT server date and the PDF's embedded creation date both correspond to 25 September 2009.

The PDF is a raster image rather than a GIS file, which is why the service territories had to be traced.

Reference layers

The county outlines and city labels are not part of the finding. They come from public-domain federal survey data and carry no claim about who delivers power.

• Texas county boundaries — U.S. Census Bureau, TIGERweb, current Counties layer (Current TIGERweb vintage).
• City label positions — U.S. Census Bureau, 2023 Gazetteer Files — Places, Texas (2023).
• United States state boundaries — Mike Bostock / us-atlas, us-atlas v3.0.1, states-10m (Census TIGER derived).

How the map was built

1. 1. Classify the source map

   The PDF was rendered to an image and the utility colors were classified using the map's own legend. County lines and labels drawn over the colored areas were filled from surrounding pixels. Areas left white on the PUCT map remained unfilled, because those areas represent locations outside the five competitive TDU territories.

2. 2. Align the map geographically

   The traced image was aligned to a Lambert conformal conic projection of Texas and vectorized into polygons. Small artifacts caused by the raster source were removed rather than treated as real service areas.

3. 3. Preserve enclaves

   Municipal and cooperative areas located inside a larger TDU territory were kept as holes in the geometry instead of being filled in. That is why the resulting map contains many separate pieces rather than five simple outlines.

4. 4. Convert the geometry to longitude and latitude

   The polygons were converted to WGS 84 longitude and latitude for publication. The conversion was checked against 20 U.S. Census Bureau place coordinates stored with the source geometry. The worst control-point residual was approximately 107 meters, which is smaller than the underlying map's own approximate tracing accuracy.

5. 5. Measure county coverage

   County coverage was calculated by comparing the published territory polygons with Texas county boundaries.

The tables and downloads are generated from the same committed territory geometry.

What the 2009 map shows

The most important finding is that Texas delivery territories are highly fragmented.

Across the five competitive TDUs, the source map produces 119 separate geographic areas and 51 municipal or cooperative enclaves. CenterPoint Energy is the only one of the five represented as a single connected area.

For this analysis, "served in full" means at least 95% of the county's drawn land area falls inside one competitive TDU. "Served in part" means between 5% and 95%. A county can appear under more than one utility.

County boundaries are a poor proxy for service territory

Of Texas's 254 counties:

• 165 contain some competitive TDU territory.
• 89 contain none.
• 153 are partly competitive and partly municipal or cooperative.
• 33 contain territory from two or more competitive TDUs.
• Only nine are at least 95% inside a single competitive TDU.

These statewide counts were reproduced using two separate measurement approaches. Minor differences remain in two per-utility county counts: the map further down this page reports Oncor at 75 counties where the table above totals 76. The one-county difference reflects the 5% threshold used for classification. The downloadable CSV includes the underlying county shares so the classification can be checked directly.

The nine counties inside a single utility

All nine, at a 95% threshold of the county's drawn land area. This is the list behind the count, so it can be checked.

The resulting map

This map represents the 2009 PUCT competitive-retail TDU sheet as traced for this project.

Areas outside the five colored territories include municipal utilities, electric cooperatives and other locations outside the competitive retail market.

The map is useful for understanding the shape of the market, but it should not be used to determine the utility serving a specific address.

What we chose not to publish

An earlier internal audit compared this map with several other utility-boundary datasets and produced additional percentages and fit statistics.

We are not publishing those figures here because the original comparison cannot be reproduced completely from the committed repository.

One helper module is missing, some intermediate files were not retained, and at least one third-party source was not recorded with a retrievable URL.

The qualitative lesson remains useful: simplified utility datasets can erase municipal and cooperative enclaves that matter in the Texas competitive market. But without a reproducible path back to the original numbers, the percentages themselves do not belong in a public research page.

We also do not publish a single square-mile figure for each utility, because this map represents competitive-retail areas, which are not necessarily the same as a utility's full certificated service territory.

Download the data

All three files are generated from the same committed territory geometry and carry their own source date and limitations.

• texas-tdu-territories.geojsonGeoJSON · 84 KB

  The five delivery territories as WGS 84 polygons, with cooperative and municipal enclaves preserved as holes. Opens in QGIS, ArcGIS, Leaflet, Mapbox or anything else that reads GeoJSON.

• texas-tdu-county-coverage.csvCSV · 14 KB

  All 254 Texas counties, with the share of each county's drawn land area falling inside each of the five territories, the competitive total, and a classification.

• texas-tdu-territory-methodology.jsonJSON · 6 KB

  The method, the projection parameters, the verification residuals, the findings, and a list of what this measurement does not establish.

The files produced by Fixed Rate Electric Plans are published under CC BY 4.0. The underlying PUCT map is identified separately as the source document. If you reuse the dataset, please keep the 2009 source date with it.

Limitations

Read these before citing anything on this page.

1. The underlying PUCT map was published in 2009. Texas utility boundaries have changed since then.
2. The dataset is a trace of a raster map, not a filed GIS boundary dataset. Edge accuracy is limited by the resolution of the source.
3. This dataset represents the five TDUs shown in the competitive-retail map. It does not individually map every cooperative or municipal utility.
4. Competitive-retail territory is not necessarily the same thing as a utility's full certificated service territory.
5. The published polygons inherit the limitations of the source map and add a smaller amount of error from reprojection.
6. Nothing here establishes a legal boundary or a current service area.
7. The PUCT's current Electric Service Area Boundaries Viewer is the better reference for current boundaries.
8. PUCT has undertaken newer GIS digitization work. If an official public dataset replaces the sources described here, this research dataset should not be treated as a substitute for it.

On the first point: the map predates the AEP Texas Central and AEP Texas North merger in 2016, the Sharyland and AEP asset swap, and Oncor's acquisition of the Sharyland distribution system in the Rio Grande Valley in 2019.

How Fixed Rate Electric Plans uses this map

The territory map is a browsing and educational tool. It is not used as the final authority for whether a home can enroll in a plan.

When a shopper searches by ZIP code, the site uses the current plan-eligibility workflow to identify the applicable market. If a ZIP can correspond to more than one delivery territory, the user is asked to resolve the ambiguity rather than the site guessing from the map.

That distinction matters because an imperfect historical map can still be useful for orientation without being allowed to determine enrollment eligibility.