Local Update of Census Addresses (LUCA)

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Local Update of Census Addresses (LUCA)

Local Update of Census Addresses (LUCA) is a partnership program established by Congress through the enactment of Public Law 103-430 (The Census Address List Improvement Act of 1994).

 

2030
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2030

Related Information

2030 Census LUCA

2030 Census Local Update of Census Addresses (LUCA) is an opportunity provided by the U.S. Census Bureau that allows tribal, state, and local governments to engage with the 2030 Census by reviewing and commenting on the Census (or LUCA) Address List prior to the 2030 Census.  

While 2030 LUCA does not officially start until 2027, governments can choose to start preparing now. Read more below in the section How to Start Preparing.

LUCA is one of the Census Bureau’s Geographic Partnership Programs that supports the 2030 Census. LUCA supports the Census Address List Improvement Act of 1994 (Public Law 103-430). 

What is LUCA?

The Census Bureau relies on a complete and accurate address list to reach every living quarter and associated population for inclusion in the decennial census. LUCA provides an opportunity for governments to participate in reviewing the Census Address List.

A LUCA review starts with governments reviewing their Address Count Listing File (also referred to as block count list) by tabulation block and comparing the totals to their own address list to determine if any discrepancies exist. Governments may find the address count meets expectations and no further review may be necessary.

Governments who agree to protect the confidentiality of the Census Address List can receive the addresses for their jurisdiction. They have the option to provide suggestions to add residential addresses, delete residential addresses that do not exist, or update the geographic location of residential addresses. The Census Address List includes street address or other descriptive information about the location where people live.

Governments who provide suggestions will receive feedback on their submission and will have the option to appeal results to the Office of Management and Budget (OMB).

Why Governments Should Participate

Participation in LUCA is not required, but governments may want to get involved for several reasons:

LUCA helps the Census Bureau develop the address list that we will use to conduct the 2030 Census. The Address Maintenance Strategy details the Census Bureau’s approach to maintaining the address frame. Some key methods we use to keep the Census Address List current include:

  • Updating the Census Address List with United States Postal Service address files.
  • Using automated change detection with imagery at moderate and high-resolution to identify change areas for further research.
  • Comparing identified areas of change to parcel data and building footprints.
  • Applying data science practices to automate and improve accuracy of address updates.
  • Using in-office research and updates to supplement automated processes.

There have been continued advancements in the tools, sources, and methods available to maintain the Census Address List, resulting in increased accuracy in most areas of the country.

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LUCA is an opportunity to provide input that helps ensure a complete and accurate address list for your jurisdiction, which is an important step towards ensuring everyone is counted in the 2030 Census.

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The Census Bureau estimates that trillions of dollars in federal funding have been distributed annually to tribal governments, states, communities, and other recipients using Census Bureau data in whole or in part. This includes data from the decennial census. Programs include health care, nutrition, highways, housing, school lunches, childcare and more. Read more about how decennial census data impacts federal funding in this report.

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What's New for 2030 LUCA

  • Governments can access Census Address Count Listing Files before LUCA starts. This will allow additional time to review resources and gather information needed to review and submit changes to the addresses in their jurisdiction.
  • LUCA participation will be digital only. There will be no paper materials for 2030 LUCA in an effort to reduce paper and costs while improving accuracy and communications. Access to materials will be web-based only.
  • Improved tools will be available to help governments participate in LUCA. This includes introducing an address matching service, web-based tools that eliminate the need for the download of software, and a secure portal to facilitate communication and registration. 
  • Governments will have more time to submit changes to the Census Address List. We have extended the review period’s duration from four months in 2020 LUCA to up to six months in 2030 LUCA.
  • We emphasize using a coverage-based and data-driven review approach. A coverage-based review will focus on determining if the Census Address List has the correct number of addresses, and if those addresses are in the correct location. A data-driven approach will enable governments to take a consistent, systematic approach to reviewing their addresses and providing updates. It will also maximize the value that LUCA adds to the 2030 Census.

How to Start Preparing

Reviewing your jurisdiction's Address Count Listing Files is an important first step. If address counts do not meet expectations in specific blocks, governments may decide to devote more time and resources to LUCA. Where address counts do meet expectations, governments may not need to request the Census Address List to conduct further review. See the Guide to Comparing Address Counts for more information.

While 2030 LUCA does not officially start until 2027, governments can choose to start preparing now by doing the following:

  • Federally recognized Tribal Nations with a reservation and/or off-reservation trust lands.
  • States.
  • Counties.
  • Cities (incorporated places).
  • Townships (minor civil divisions).

Highest elected/appointed officials from active, functioning, legal governments can designate the person who will represent their jurisdiction. This may include direct employees, interns, contractors, or designating alternate reviewers, such as county, state data center, or regional planning agency.

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Local address sources, such as building permits, E-911 address files, local utility records, annexation records, or taxation files may be available. The address list should include location information, such as latitude and longitude. Community-based organizations may also be a resource to identify any missing or hidden housing.

Only residential living quarters will be included in the frame for 2030 Census operations, so care should be taken to exclude other addressed structures, such as libraries, fire hydrants, or businesses.

  • You can use the Current Address Count Listing Files and the Housing Unit Change Viewer (2020 to current) to review address changes in your community compared to the 2020 Census. See Data Gem: Tracking Housing Trends with the Housing Unit Change Viewer.
  • Additionally, the Participant Address List Template will help ensure that your address data meets the minimum requirements should you decide to submit updates during the address review and update submission period.
  • Access these in the section below: Resources You Can Use to Prepare
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The Census Bureau uses a variety of sources to maintain the address list. Consider publishing address data in the National Address Database (NAD) and sharing address and parcel data online.

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Some governments may lack the time or resources to conduct a thorough analysis of address data. Consider collaborations with your county, state, state data center, or regional planning agency. Funding is not available from the Census Bureau but may be available from other sources.

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Important Dates

Starting now, governments can choose to begin preparing for LUCA by following the steps outlined in the section above, How to Start Preparing.

  • Governments receive materials about LUCA, are invited to set up accounts, and register.
  • Governments conduct block level address count comparisons and have option to practice an address level review.
  • Submissions will not be accepted at this time, but there will be opportunities for training and hands-on practice.
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  • Continued opportunity to learn about LUCA, set up accounts, and register.
  • Governments conduct a block level address count review and can review the Census Address List and submit suggestions to add, delete, or update the geographic location of residential addresses.
  • There will be a firm deadline of March 31, 2028, for LUCA submissions so that the Census Bureau has time to process submissions and ensure all eligible addresses are included in the 2030 Census.
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  • Governments receive address-level feedback on how their submissions are incorporated into the Census Address List.
  • Governments must submit any appeals within 60 calendar days of receiving feedback to the Office of Management and Budget (OMB).
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  • The closeout phase marks the end of governments’ access to confidential LUCA materials.
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What to Expect

LUCA Invitations will be sent at the beginning of May 2027, starting the first phase of LUCA, called LUCA Prep. During this phase there will be an opportunity to register, receive training, conduct a Block Review with preliminary census address counts by block, provide a LUCA Prep Response, and practice an Address Review. Address materials will be available for practice through August 2027.

LUCA Review is conducted October 2027 through March 2028. This phase starts with the LUCA Review Invitation, and a continued opportunity to register and receive training. During LUCA Review, updated census address counts by block will be available for Block Review. LUCA Review continues with the LUCA Review Response. If the Census Address List is requested, there will be an Address Review and LUCA Submission.

  • In May 2027, the Census Bureau will send Tribal Leaders and Highest Elected/Appointed Officials an email invitation to participate in LUCA. Copies of the invitation will be sent to 2020 LUCA contacts and key stakeholders for awareness and possible assistance in reaching appropriate contacts. The Census Bureau will email governments a second invitation in October 2027 at the start of LUCA Review.
  • Invitation emails will direct LUCA participants to the Census Bureau’s Geography Division Partner Portal (GDPP) and the LUCA webpage for more information on how to get started.
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  • Tribal Leaders and Highest Elected/Appointed Officials will be invited to identify a LUCA Liaison to be a central point of contact for LUCA for their jurisdiction. Multiple LUCA Reviewers can also be identified.
  • Local governments are encouraged to collaborate with larger governments, such as a county or state. Local governments may not need to register separately for LUCA and may be added as a reviewer for the larger government.
  • The first step to register for LUCA is to create an account for the GDPP. A unique email address will be needed for each LUCA reviewer, and there will be several steps to complete registration. It is recommended that the registration process be started by February 4, 2028.
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  • Details about LUCA participation will be available on the LUCA webpage starting in May 2027. This includes:
    • A LUCA overview guide and other reference materials.
    • Recorded LUCA training, available to watch on demand.
    • Virtual training sessions offering the opportunity for questions and answers.
    • Additional training and materials will be added in October 2027 to support Digital Download options, and again in March 2029 to accompany LUCA Feedback.
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  • Both LUCA Prep and LUCA Review start with a Block Review to determine if overall and localized address counts meet expectations. In many cases this will be done by comparing census address counts by block to expected block totals from government address lists. In some cases, the review may be conducted by using an interactive map viewer to browse specific areas of concern (based on community knowledge). Tools to support this process are available now. See the Guide to Comparing Address Counts by Block. Results of the block level review will inform the LUCA Response and next steps. 
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  • Governments should respond to indicate their participation in both the LUCA Prep and LUCA Review phases.
  • A LUCA response lets the Census Bureau know if the government conducted LUCA research and if the block counts reviewed in Block Review met expectations, if the government is requesting an Address Review, or if the government is not participating in LUCA Review for other reasons. 
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  • Governments that indicate that it would be beneficial to review the Census Address List in their LUCA Response, will have the opportunity to conduct Address Review within their jurisdiction.
  • Governments participating in the Address Review are required to complete the LUCA Security Checklist and Confidentiality Agreement.
  • Address Review is available during both LUCA Prep (May 2027 – August 2027) and LUCA Review (October 2027 – March 2028).
    • During LUCA Prep, only the Geographic Update Partnership Software (GUPS) Web will be available to support review of the Census Address List. This supports hands-on-training and is for practice only.
    • During LUCA Review, the LUCA Liaison will select the product preference in the GDPP during LUCA Response. LUCA participants will be able to review the Census Address List using GUPS Web or can download the Census Address List via Digital Download to use with their own tools. To use Digital Download, LUCA participants will need their own Geographic Information System (GIS) tools and will need to comply with additional security measures.
    • The Census Address List available in LUCA Review will reflect any updates made to the Census Bureau’s address inventory since LUCA Prep materials were created.
  • During Address Review, authorized participants will be able to review the Census Address List, and provide suggested adds, deletes, updates to geographic coordinates, or modifications to the type of living quarters.
  • Quality checks will be available in both LUCA Prep and LUCA Review to support accurate formatting and ensure sufficient information for LUCA Submission.
  • Each person with access to the Census Address List may retain the list and other 2030 LUCA materials until work on 2030 LUCA has concluded. Once LUCA participation ends, LUCA Closeout activities must be completed as outlined below for participants who received access to the Census Address List.
    • For access via GUPS Web only, the Census Bureau will automatically conduct closeout activities, and no further action is needed.
    • For participation using Digital Download during any portion of LUCA Review, all 2030 LUCA Title 13 materials need to be destroyed as outlined in the LUCA Security Checklist and Confidentiality Agreement Guidelines and the LUCA Destruction of Title 13 Materials form completed via the GDPP.
  • It is recommended that all forms needed to conduct an Address Review be completed no later than February 18, 2028, to allow participants time to complete their Address Review and provide submissions. 
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  • LUCA Submissions will be accepted during the LUCA Review phase (October 2027 – March 2028).
  • The LUCA Submission includes suggested adds, deletes, updates to geographic coordinates, or modifications to the type of living quarters.
  • Participants will need to complete quality checks to ensure minimum criteria prior to the final LUCA Submission.
  • Please ensure submissions are complete, as only one LUCA Submission will be accepted.
  • Participants can submit LUCA updates directly via the GUPS Web software or by following the instructions provided if using Digital Download.
  • All participants submitting LUCA updates to the Census Bureau will share the same submission deadline of March 31, 2028.
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Resources You Can Use to Prepare

These resources are available now to view census address data and start developing your own residential address list. Additional details and information on how to use these resources are available in the links below.

I’m looking for... Resources 
Information on the changes between 2020 Census housing unit counts and the latest currently available counts Housing Unit Change Viewer – The Census Bureau continuously makes updates to our address database. This interactive map application shows the change in the number of housing units from the 2020 Census to present for states, counties, tracts, and blocks.

Data Gem: Tracking Housing Trends with the Housing Unit Change Viewer – The Census Bureau tracks housing changes across the country. Watch this demonstration of how to use the Housing Unit Change Viewer, which is an interactive tool to spot trends and see where communities are growing.
Address counts by block. These can be used to determine if the Census Bureau counts meet my expectations Current Address Count Listing Files – These files include total housing units and total group quarters counts by census tabulation block. Downloads are available for each state.

Current Address Count Listing Files Viewer – This viewer supplements the Current Address Count Listing Files and allows users to zoom in and click on a Census block to see characteristics.

Data Gem: Discover Your Neighborhood with the Current Census Address Count Listing Files Viewer – Watch this demonstration of how to use the Address Count Listing Files Viewer to zoom in to a census block, search the area, and look up current housing totals.
Information on getting started to prepare an address list Participant Address List Template – This template demonstrates how to organize address information when developing an address list. This format is necessary for using the Census geocoder and is also recommended in preparing for LUCA.
Information about what living quarters are and what is included in the Census Address List Baseline 2030 Census Living Quarters Definitions and Code Lists – Living quarters definitions specify how the Census Bureau categorizes and assigns code values to different types of living quarters.
Examples to compare address counts by using spreadsheets or spatial data Guide to Comparing Address Counts by Block – A guide with examples to make your own comparison to Census Address Count Listing Files.

Address Geocoder – This tool can be used to identify current Census tabulation blocks for provided addresses.

LUCA Geocoder and Block Count List User Guide – A guide with instructions on how to use the Address Geocoder and the Address Count Listing Files (also known as Block Count Lists) tools to support participants in LUCA. These tools allow participants to verify and geocode address lists and to generate block count lists for geocoded addresses.
Federal Register Notice with 2030 LUCA plans 2030 LUCA Federal Register Notice (FRN) – The 60-Day FRN provides the public with an opportunity to review and comment on the plans for 2030 LUCA.
Other links of interest Response Outreach Area Mapper (ROAM) – This tool identifies low response scores at the Census tract level.

Address Maintenance Strategy – Overview of methods and sources to maintain the coverage and accuracy of the Census address list.

2020 LUCA Participants Viewer – This map displays registered 2020 LUCA participant entities.

2020 LUCA Respondents List – This list displays the governments that submitted a response for 2020 LUCA. It includes the 2020 LUCA Liaison’s Title and Department Name.

Getting Ready for 2030 LUCA Presentation – This slide deck provides an overview of LUCA with a focus on what governments can do to prepare. Getting Ready for 2030 LUCA Presentation Script – This script accompanies the Getting Ready for 2030 LUCA Presentation.

Have Questions?

See 2030 LUCA FAQs and Glossary/Key Terms.

If you have additional questions regarding 2030 LUCA, email us at [email protected].

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Page Last Revised - June 4, 2026