TIGER
Contents
TIGER stands for Topologically Integrated Geographic Encoding and Referencing. TIGER files are a comprehensive digital geographic database created and maintained by the U.S. Census Bureau. They serve as the foundational geographic framework for all census activities and are a fundamental resource for anyone working with U.S. geographic data.
Here's a breakdown of what TIGER files are and what they contain:
What are TIGER files?
TIGER files are not census data themselves; rather, they are the map data that provides the geographic context for census data. They are a collection of files that describe the physical and cultural features of the entire United States, Puerto Rico, and the Island Areas.
The data is structured in a way that allows it to be used with Geographic Information System (GIS) software to create maps and perform spatial analysis. The files represent geographic features using vector data, such as points, lines, and polygons.
Key features and data included in TIGER files:
| • | Boundaries: This is one of the most important components. TIGER files contain the boundaries for all types of census-related geographic areas, including: |
| o | Legal boundaries: States, counties, cities, and incorporated places. |
| o | Statistical boundaries: Census tracts, block groups, and census blocks (the smallest geographic unit for which the Census Bureau tabulates data). |
| o | Political boundaries: Congressional districts, state legislative districts, and voting districts. |
| • | Physical features: TIGER files also include an extensive network of physical features, such as: |
| o | Roads and streets (including address ranges for most streets). |
| o | Railroads. |
| o | Hydrography (rivers, lakes, and other water bodies). |
| • | Geographic identifiers (GEOIDs): Each geographic entity in a TIGER file has a unique identifier (GEOID). This is the key that allows users to link the geographic boundaries from the TIGER files to the demographic and economic data from the various censuses and surveys (like the Decennial Census or American Community Survey). |
Uses of TIGER files:
TIGER files are a core resource for a wide range of applications:
| • | Mapping: They are used to create digital maps for both general and specialized purposes. |
| • | Redistricting: TIGER files, particularly those with census block boundaries, are essential for the redistricting process. |
| • | Spatial analysis: Researchers and planners use TIGER files to analyze how demographic data is distributed across a geographic area. |
| • | Navigation and logistics: The road network data within TIGER files has been a foundational element for many commercial and open-source mapping services. |
| • | Emergency services: They can be used by emergency responders for planning and route finding. |
The Census Bureau continuously updates and refines the TIGER database, and the files are publicly available, typically in formats like shapefiles or geodatabases, making them an invaluable, free resource for government agencies, private businesses, and the public.
Topologically Integrated Geographic Encoding and Referencing
Details about TIGER & Use
Vintage 2025 TIGER files are released in TL (most detailed, August 2025) and CB (Smoothed, April 2026).