Demographic data refer to the Decennial Census and other surveys of individuals and households administered by the Census Bureau. Compared to their public use counterparts, the internal data files include more detailed geographic information, generally to the block level for the Decennial Census and census-tract level for surveys, as well as less restrictive top-coding. The following table lists person and household based data, the frequency of data collection, the unit of enumeration, the years of data available, and the sponsoring federal agency. Access to these data will only be granted to qualified researchers on approved projects with authorization to use specific data sets. All external project researcher access to restricted–use data occurs at one of the secure Federal Statistical Research Data Centers or, where authorized, through the secure Remote Access Program. 

Some Census Bureau data collections are sponsored in whole or in part by other federal agencies. Sponsorship of data collections may also change over time. External research projects using these data may require permission of the sponsoring agency.

You can apply for access to restricted-use microdata at FSRDCs via the Standard Application Process (SAP) Portal at sap.nsf.gov. The SAP Portal is a web-based data catalog and common application that serves as a “front door” to apply for confidential data from any of the 16 principal federal statistical agencies and units for evidence building purposes. To learn more about the SAP, please visit the Standard Application Process Overview webpage. Information about applying for access to restricted-use Census Bureau microdata in the FSRDCs using the SAP portal is available on the Census Bureau’s Standard Application Process website.  

Note: the SAP Portal has the definitive list of restricted-use Census Bureau datasets available to potential FSRDC researchers. Datasets are added and removed from the SAP portal as their availability status changes.

Assistance from an FSRDC administrator will greatly reduce the need for future revisions to your application. If you are unsure which FSRDC to contact or have a general question, please reach out to the Census Bureau at [email protected].

*The National Longitudinal Mortality Study (NLMS) consists of a database developed for the purpose of studying the effects of demographic and socio-economic characteristics on differentials in U.S. mortality rates. The NLMS is a unique research database in that it is based on a random sample of the non-institutionalized population of the United States. It consists of Annual Social and Economic Supplements which cover the period from March 1973 to March 2011, Current Population Surveys for February 1978, April 1980, August 1980, December 1980, and September 1985, and one 1980 Census cohort, 39 cohorts in all. These are combined with death certificate information to identify mortality status and cause of death.