The Census Bureau relies on a complete and accurate address list to reach every living quarters and associated population for inclusion in the census.

The 2020 Census LUCA operation was the only opportunity offered to tribal, state, and local governments to review and comment on the U.S. Census Bureau's residential address list for their jurisdiction prior to the 2020 Census.

The LUCA schedule spanned from January 2017 to September of 2019, with closeout efforts occurring through June 2020. The Census Address List Improvement Act of 1994 (Public Law 103-430) authorized the LUCA.

Active, functioning governments were eligible to participate in 2020 LUCA for areas including:

• Federally recognized tribes with a reservation or off-reservation trust lands;
• States;
• Counties;
• Cities (incorporated place); and
• Townships (minor civil divisions).

If governments lacked the resources to participate in 2020 LUCA, they were able to arrange for a higher level of government, such as county, or an organization, such as regional planning agency or council of governments, to conduct their review.