Skip Main Navigation Skip To Navigation Content

American Community Survey

Census.govAmerican Community Survey › Data & Documentation: Public Use Microdata Sample (PUMS)
Skip top of page navigation

Public Use Microdata Sample (PUMS)

The American Community Survey (ACS) Public Use Microdata Sample (PUMS) files are a set of untabulated records about individual people or housing units. The Census Bureau produces the PUMS files so that data users can create custom tables that are not available through pretabulated (or summary) ACS data products.

Summary products, such as the tables and profiles accessible via American FactFinder (AFF), show data that have already been tabulated for specific geographic areas.

PUMS files, in contrast, include population and housing unit records with individual response information such as relationship, sex, educational attainment, and employment status.

Confidentiality of PUMS
The confidentiality of ACS respondents is protected through a variety of means, ensuring that it is impossible to identify individuals who provide any response, yet making sure the results are still useful. The PUMS records do not contain names, addresses, or any information that can identify a specific housing unit, group quarter, or person.

Why Use PUMS?
PUMS files are perfect for people, such as students, who are looking for greater accessibility to inexpensive data for research projects. Social scientists often use the PUMS for regression analysis and modeling applications.

What's Available and How Can I Access PUMS?
The Census Bureau produces 1-year, 3-year, and 5-year ACS PUMS files. The 3-year and 5-year PUMS files are multiyear combinations of the 1-year PUMS file with appropriate adjustments to the weights and inflation adjustment factors. The PUMS files are accessible via American FactFinder, the Census Bureau's FTP site, and DataFerrett. Statistical software is needed to use the PUMS files from American FactFinder and the FTP site.

Need Help with PUMS?
Learn more about PUMS in the Compass Products What PUMS Data Users Need to Know handbook and Introduction to the PUMS training presentation. You can also learn more about creating ACS custom tables using DataFerrett by viewing Part 1 and Part 2 of our new videos.

Geographic Areas Available
Region, Division, State, and Public Use Microdata Areas (PUMAs) are the only geographic areas identified in the ACS PUMS. Of these, Public Use Microdata Areas (PUMAs) are the most detailed geographic areas available.

[PDF] or PDF denotes a file in Adobe’s Portable Document Format. To view the file, you will need the Adobe® Reader® Off Site available free from Adobe.    The letters PPT indicate a document is in the Microsoft® PowerPoint® Format (PPT). To view the file, you will need the Microsoft® PowerPoint® Viewer Off Site available for free from Microsoft®.    This symbol Off Site indicates a link to a non-government web site. Our linking to these sites does not constitute an endorsement of any products, services or the information found on them. Once you link to another site you are subject to the policies of the new site.

Source: U.S. Census Bureau | American Community Survey Office | Email ACS | Last Revised: April 13, 2015
Give us your feedback on this website!