This Insight accompanies the Congressional District Geography Workbook, a Microsoft Excel file that congressional users can download from CRS.gov. The workbook provides information about U.S. House districts as configured in the 119th Congress (2025-2026).
It supersedes the version published for the 118th Congress: CRS Insight IN12393, Congressional District Geography Workbook (118th Congress): An Interactive Tool for Congressional Users, by Ben Leubsdorf.
This new Workbook incorporates updated datasets, new categories of geographic areas and features, and revised district boundaries in five states (Alabama, Georgia, Louisiana, New York, and North Carolina).
The Congressional District Geography Workbook contains information about selected geographic areas and features located inside each of the 435 congressional districts across all 50 states. It also includes information for the District of Columbia, Puerto Rico, American Samoa, Guam, Northern Mariana Islands, and U.S. Virgin Islands.
It contains 38 categories of geographic areas and features.
A geographic area or feature is associated with a specific congressional district when it is located fully or partly inside that district's boundaries. An area or feature may be located entirely within a single district or split between two or more districts.
Eleven categories do not include any locations in the five U.S. territories: bikeshare systems, border crossings, food assistance, major sports venues, museums, national laboratories, Native American areas, private schools, spaceports, train stations, and tribal governments. Other categories may provide limited coverage of locations in the territories.
The workbook, when downloaded and opened in Microsoft Excel, contains five sheets that can be accessed via tabs at the bottom of the screen.
The workbook sheets are formatted for ease of use and are password-protected to prevent changes.
CRS can provide Members and staffers with additional analysis and information upon request (e.g., points of interest not included in the Workbook, directory-type contact information for selected categories, or the extent of overlaps for areas split among more than one district).
CRS acquired data from the sources described below in August 2025, unless otherwise noted. These datasets were the most recent available, though they may have been compiled or updated at different times. When direct crosswalks to 119th Congress districts were not available, CRS generally used the tigris and sf packages in the R statistical programming language to match longitude and latitude coordinates, as provided by agencies or geocoded by CRS, with a corresponding congressional district. Not all categories may be comprehensive, and the workbook may contain errors, including potential mistakes present in the source datasets.
The U.S. Army Corps of Engineers (USACE) at the U.S. Department of Defense (DOD) provided information directly to CRS in December 2024 about ports in each district. This category includes ports on rivers and lakes as well as seaports and port statistical areas, which are defined in legislation and may extend well beyond the port's physical infrastructure. USACE also provided coordinates for dams via the National Inventory of Dams. The Dam list in the workbook is limited to dams designated as having high hazard potential, meaning the loss of at least one life is probable from a dam failure. Each dam's name is accompanied by information about the dam's primary purpose, if available. Additional information is available in CRS Report R45981, Dam Safety Overview and the Federal Role, by Anna E. Normand, and information about other dam locations is available in the National Inventory of Dams.
The Bureau of Indian Affairs (BIA) in the U.S. Department of the Interior (DOI) provided coordinates for tribal government offices via its Tribal Leaders Directory. This category contains headquarters locations for the 574 American Indian and Alaska Native entities currently recognized by the federal government, excluding affiliates and other entities. Entity names are generally as they appear in the BIA's December 2024 list of "Indian Entities Recognized by and Eligible To Receive Services From the United States Bureau of Indian Affairs." Because these offices are represented by point locations, their district assignments may not capture the full extent of a tribe's authority. The separate Native American Area category includes reservation boundaries and tribal statistical areas. Additional information is available in CRS Report IR10001, Tribal and Other Indigenous Lands in the 119th Congress, by Mariel J. Murray and Mainon A. Schwartz.
The Bureau of Transportation Statistics (BTS) at the U.S. Department of Transportation (DOT) provided coordinates for airports, bikeshare systems, border crossings, ferry terminals, spaceports, train stations, and transit systems (based on transit agency office and stop locations). The Airport list is limited to public-use airports eligible for federal funding as listed in the Federal Aviation Administration's (FAA's) National Plan of Integrated Airport Systems (NPIAS). The Bikeshare System list is based on active docking-station locations and does not include dockless scooters or bikes. The Border Crossing list is based on 2024 and 2025 entry statistics provided to BTS by U.S Customs and Border Protection (CBP), and includes 84 ports at the U.S.-Canada border and 28 border ports between the U.S. and Mexico. Each border port can include multiple physical crossing locations (e.g., the Beecher Falls port in Vermont covers stations in Canaan, VT and Pittsburg, NH), and this list does not include all ports of entry to the United States. The Spaceport list includes commercial and federal space launch and reentry sites. The Train Station list excludes Amtrak-operated bus stops and includes six Brightline stations in Florida. The Transit System category assigns an agency to any congressional district that contains the agency's office or at least one bus, subway, or other stop served by that agency. Because facilities are represented by point locations, their district assignments may not capture the full extent of their physical footprints.
The Census Bureau in the U.S. Department of Commerce provided information about counties, county subdivisions, Native American areas, places, and school districts via its Congressional District Relationship Files, which contain crosswalks between 119th Congress congressional districts and geographic areas used in the 2020 census. For Connecticut, the County category includes both historical counties and modern planning regions. The Native American Area category includes federal and state reservations, off-reservation trust lands (ORTLs), Hawaiian Home Lands (HHLs), Alaska Native Village Statistical Areas (ANVSAs), Oklahoma Tribal Statistical Areas (OTSAs), State Designated Tribal Statistical Areas (SDTSAs), and Tribal Designated Statistical Areas (TDSAs).
CRS matched state legislative districts in the 50 states, the District of Columbia, and Puerto Rico to congressional districts using the Census Bureau's 2024 State Legislative Block Equivalency Files (BEFs) and 119th Congress BEFs. Relationships between state legislative and congressional districts were established based on shared census blocks, with split blocks assigned to all matching districts.
The DOD's Defense Installations Spatial Data Infrastructure (DISDI) program provided information directly to CRS in November 2024 about military installations in each congressional district. This category includes ranges and training areas. Some facilities are split between two or more districts. The source dataset excludes some facilities due to national security concerns as well as relatively small facilities, including many National Guard and Reserve sites. It also excludes U.S. Coast Guard facilities, which fall under the Department of Homeland Security (DHS).
The Energy Information Administration (EIA) at the U.S. Department of Energy (DOE) provided coordinates for power plants. The dataset contains all operable electric generating facilities in the 50 states, the District of Columbia, and Puerto Rico with nameplate capacity of at least 1 megawatt. Plant names are accompanied by information about that facility's energy source(s).
The Environmental Protection Agency (EPA) provided coordinates for charitable food assistance organizations via its Excess Food Opportunities Map, municipal solid waste landfills via its Landfill Methane Outreach Program database, and federal Superfund sites via its Superfund National Priorities List (NPL) Where You Live Map. The nonprofit organizations Feeding America and Hunger Free America provided data to EPA on food bank, food pantry, and soup kitchen locations. This list is probably not comprehensive; users can consult local community contacts for further information about area organizations. Information about federal programs that support such organizations is available in CRS Report R45408, The Emergency Food Assistance Program (TEFAP): Background and Funding, by Kara Clifford Billings, and CRS Report R48124, Connecting Charitable Food Assistance Organizations to Federal Funding Information and Resources, by Sarah K. Braun and Alyse N. Minter. Some landfills were matched with districts based on states associated with a single congressional district, while roughly 12% of the more than 2,600 landfills in the dataset could not be matched with any district due to missing coordinates and are excluded. Also, each landfill's name is accompanied by information about its current status (open, closed, or unknown). The list of Superfund sites comprises all locations currently on the EPA's National Priorities List (NPL) and excludes proposed and deleted sites.
The U.S. Forest Service in the U.S. Department of Agriculture (USDA) provided information directly to CRS in January 2025 about national forests and other National Forest System units in each district, adapted from the agency's Land Areas of the National Forest System reports. The National Forest System includes national forests, national grasslands, land utilization projects, purchase units, research and experimental areas, and other areas. Additional information is available in CRS Report R43872, National Forest System Management: Overview and Issues for Congress, by Anne A. Riddle.
The U.S. Geological Survey (USGS) at DOI provided coordinates for state capitol buildings as part of its National Map. The USGS dataset included territorial legislature buildings, and CRS manually added the John A. Wilson Building in the District of Columbia.
The Government Publishing Office (GPO) provided information about federal depository libraries in each congressional district via the Federal Depository Library Directory.
The U.S. Department of Health and Human Services (HHS) provided coordinates for Head Start service locations. Some locations may appear multiple times if they offer more than one program at the same address (e.g., separate entries for an Early Head Start program and a Head Start Preschool program hosted in the same building). Additional information is available in CRS In Focus IF11008, Head Start: Overview and Current Issues, by Karen E. Lynch.
DHS provided coordinates for emergency operations centers (EOCs), via the Federal Emergency Management Agency (FEMA) for facilities operated by state and territorial governments and via the Homeland Infrastructure Foundation-Level Data (HIFLD) repository for facilities operated by local governments such as cities, counties, and tribes.
The U.S. Department of Housing and Urban Development (HUD) provided crosswalks between congressional districts and five-digit ZIP codes via its HUD USPS ZIP Code Crosswalk Files. Note that this should not be taken as a definitive placement of ZIP codes in congressional districts, as slight differences in methodology may produce different results.
The Institute of Museum and Library Services (IMLS) provided information about and coordinates for public libraries (from fiscal year 2022) and museums (from 2018). Each library's name is followed by its system name in parentheses, unless the two names are identical. The Museum category includes related institutions such as arboretums, art galleries, historical societies, and zoos.
The Internal Revenue Service's (IRS's) Exempt Organizations Business Master File Extract contained mailing address information for more than 6,700 chambers of commerce (tax-exempt 501(c)6 organizations with classification code 3) registered with the U.S. Department of the Treasury. CRS geocoded addresses to generate longitude and latitude coordinates, then matched each point with a corresponding congressional district. In addition, some addresses were matched with districts based on states and ZIP codes associated with a single congressional district. District locations could not be determined for roughly 9% of organizations, most listing P.O. boxes as addresses; those groups are omitted.
The Mine Safety and Health Administration (MHSA) at the U.S. Department of Labor (DOL) provided coordinates for active and intermittently active coal, metal, and nonmetal mines via its Mine Data Retrieval System. Some mines were matched with districts based on states associated with a single congressional district. Roughly 0.5% of active and intermittently active mines could not be matched with any district due to missing or inaccurate coordinates and are omitted. Each mine's name is accompanied by information about its primary commodity. Because mines are represented by point locations, congressional-district assignments may not capture the full extent of a mine's physical footprint.
The National Center for Education Statistics (NCES) at the U.S. Department of Education provided information about public schools (elementary and secondary), private schools (elementary and secondary), and postsecondary institutions (such as colleges and universities) via its Education Demographic and Geographic Estimates (EDGE) program. The most recent files available were 2023-2024 data for public and postsecondary schools and 2021-2022 data for private schools. Because schools are represented by point locations, congressional-district assignments may not capture the full extent of a campus. In addition, the Postsecondary Institution category may include administrative offices that are not necessarily associated with student populations.
The National Park Service in DOI provided information about national parks and other National Park System units in each district. The National Park System includes national parks, battlefields, historic sites, preserves, monuments, memorials, and other areas. Additional information is available in CRS Report R41816, National Park System: What Do the Different Park Titles Signify?, by Laura B. Comay.
The U.S. Department of Veterans Affairs (VA) provided coordinates for VA facilities via its VA Facilities API. These include but are not limited to Veterans Benefits Administration regional offices, national cemeteries, state and tribal veterans cemeteries, soldiers lots, VA medical centers, community-based outpatient clinics, vet centers, and mobile vet centers.
The Major Sports Venue category includes U.S. home arenas and stadiums used by professional baseball (MLB and MiLB), basketball (NBA, WNBA, and G League), football (NFL), hockey (NHL, PWHL, AHL, and ECHL), and soccer (MLS and NWSL) teams, as well as additional stadiums with seating capacity of 30,000 or more. The FAA provided coordinates for stadiums, and CRS assembled and geocoded addresses for smaller facilities in December 2024-August 2025.
The National Laboratory category comprises 42 offices and other facilities described on the individual websites of the 17 national laboratories overseen by DOE. These include 10 laboratories under the DOE Office of Science and three national security laboratories under the National Nuclear Security Administration (NNSA). Additional information is available in CRS In Focus IF12692, Department of Energy (DOE) Office of Science, by Todd Kuiken, and CRS Report R48194, The U.S. Nuclear Security Enterprise: Background and Possible Issues for Congress, by Anya L. Fink. CRS assembled and geocoded addresses for each facility in July 2025. Because each facility is represented by a point location, its district assignments may not capture the full extent of its physical footprint.
This Workbook was initially published in January 2025.
It may be updated again in 2025 and 2026 to incorporate changes to its underlying datasets. Any updates will be noted in this space so users are aware when a new version is available to download.
CRS plans to publish a new version of the Congressional District Geography Workbook in 2027 to incorporate any changes to congressional-district boundaries for the 120th Congress (2027-2028), as well as updates to source datasets.