The California Census Office has created this interactive map to view California census tracts and block groups. Many California residents live in areas that, based on demographic, socioeconomic and housing characteristics, may be hard to count in the 2020 Census. The California Census Office has created this interactive map that shows California census tracts and block groups shaded by their California Hard-to-Count Index, a metric that incorporates 14 variables correlated with an area being difficult to enumerate. Click here to start using the map

HTC Map image

Census tracts and block groups with higher CA-HTC indexes likely will pose significant challenges to enumerate in 2020, while tracts and block groups with lower indexes should be easier to count.

Click on the map to get started!

Data download: Click either of the links to download files of the latest version of the California Hard-to-Count Index at the tract and block group levels.

The U.S. Census Bureau released its mail contact strategies, identifying how different parts of the U.S. will be invited to respond to the 2020 Census. The interactive map shows how different parts of California will be invited to respond. Click the map or visit this link for more information. In addition, people can enter an address in the search bar or use the bookmark to quickly view different parts of the state.

US Census Bureau Contact Strategies Map

Click here to learn more about the mail contact strategy.

How to Use the Map

  • Click on “Interactive CA Hard-to-Count Map,” which will take you to
  • Click on the a tract or block group to learn more information.

– A box opens up with information on that census tract or block group.
– Open the data attribute table by clicking on the three dots in the popup box’s bottom-right corner. (You can also open the table by clicking on the arrow at the bottom of the screen)

  • Organize the data through various filters and settings –

Widgets in the map’s upper-left corner:

Search bar – search by county or address.
Basemap Gallery – choose between different basemaps, such as imagery or StreetMap.
Bookmark – select a city to zoom to specific parts of the state
Draw – draw a circle or other shape in an area of focus
Add Data – upload data in .shp or another file format.
Print – export a .pdf of the view to save and/or print.

Widgets in the map’s upper-right corner:

Filter tool – identify census tracts or block groups with HTC indexes above a certain value. Use the filter in the attribute table to further refine a selection.
Legend button – see the ranges of CA-HTC Index classes
Layer list:
– Congressional districts
– State Senate districts
– State Assembly districts
– CA HTC Index tract level
– CA HTC Index block group level

  • Want to download a slice of data? Go to the attribute table, zoom in to a desired area on the map or click on “options” and make a filter expression. Then click “export all to CSV.”
  • Need information not shown here? Go to the U.S. Census Bureau American Fact-Finder site

Sources: CA HTC Index variables, 2013-2017 American Community Survey 5-year estimates; California Public Utilities Commission; 2018 Planning Database