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Cornell Program on Applied Demographics

Census 2020: What State and Local governments need to Know


2020 Addresses and the Master Address File (MAF)


Since the 1960 Decennial Census, the U.S. Census Bureau sends questionnaires by mail, rather than collecting information by going door-to-door. This method has been used more and more throughout the decades and since the 1990's the Census Bureau maintains an address database, called the Master Address File. In 2010 an estimated 90% of households received their questionnaire by mail. The 2010 Type of Enumeration map shows the areas questionnaires were send out by mail in 2010. More on the development of the 2020 Type of Enumeration Areas can be found in 2020 Census Detailed Operational Plan for: 6. Geographic Programs Operation (GEOP) – 6-1. Geographic Delineations Component (GEOP/GD).

Definition Master Address File:
The Census Bureau’s official inventory on known living quarters (HUs and GQ facilities) and selected non-residential units (public, private, and commercial) in the United States. The file contains mailing and location address information, geocodes, and other attribute information about each living quarters. The Census Bureau continues to update the MAF using the USPS Delivery Sequence Files and various automated, computer assisted, clerical, and field operations.

The success of the Decennial Census count depends very much on the quality and completeness of the address file. Since addresses are assigned and maintained at the local level, the Census Bureau has several programs to involve the local and state governments in maintaining and reviewing the MAF.

MAF maintainance programs between 2010 and 2020

  • With information provided by the US Postal Service
    Twice a year the Census Bureau receives the Delivery Sequence File from the Postal Servce and integrates the changes in that file into the MAF
  • In office canvassing
    This is one of the innovation areas for this decade. See for example this blog entry
  • In field canvassing
  • With information provided by local and state governments.
    In past decades the Census Bureau relied mostly on the LUCA program to get address data from local sources, but this decade it developed the Geographic Support System (GSS) that invites local and state governments to share address information. See more in the section on GSS
  • With information provided by Commercial sources

2020 MAF Review and Update programs

  • New construction
    The New Construction program is an opportunity for governments to submit city style mailing addresses for units that are constructed after other programs end but before Census Day (April 1, 2020). See more in the section on New Construction
  • Local Update Census Addresses
    LUCA is a once–a-decade opportunity for local designated representatives to review the addresses that will be used to conduct the Decennial Census. See more in the section on LUCA
  • Count Review
    Count Review is an operation where state representatives from the Federal State Cooperative on Population Estimates (FSCPE) have an opportunity to review the final address frame and later on the preliminary Group Quarters tabulations. See more in the section on Count Review

Last modified: February 2, 2018