How To Prepare For The 1940 U.S. Census

by Thomas MacEntee | Mar 6, 2012

Thomas MacEntee

[UPDATE: This Expert Series article was published before the release of the 1940 U.S. Census. You can now use the 1940 census, including the everyname index, for free at]

For genealogists and family historians, it has been difficult to avoid all the news and, as some say, "hype," about the 1940 US Census. Most of us know that on April 2, 2012, at 9:00 a.m. Eastern, the National Archives and Records Administration (NARA) will release the images for the 1940 U.S. Census. has partnered with NARA to host the images at which will be the only website hosting all of the 1940 Census images on April 2nd.

What you may not know is that you will not have access to an index of the images, at least not for several weeks. Do you know how you will find your family members quickly using just the 1940 U.S. Census images? Do you know what information to gather now before April 2, 2012? Using the information below, you can learn how to get started and what tools will assist you in finding the 1940 U.S. Census images you need.

The 1940 U.S. Census - What You'll Find

The 1940 U.S. Census and the more than 132 million names listed within its pages represent a snapshot of American life on April 1, 1940. You can access a sample census page on at Census Research.

While the information in the census is very similar to that gathered in the 1930 U.S. Census and previous years, here are some valuable data points for genealogists:

  • Name of informant: Learn who actually provided the information to the census enumerator. In previous censuses, a common assumption was that the informant was the head of household.
  • Highest school grade completed: This information goes beyond the basic "can read" or "can write" questions of previous censuses.
  • Place of residence in 1935: The United States experienced a major economic and social upheaval during the Great Depression. Migration patterns can be traced using the data from this question.

Sampling - the practice of asking a special sub-set of questions to a small group of respondents - occurred for the first time during the 1940 U.S. Census. Respondents listed on lines 14 or 29 were asked questions related to:

  • Birthplace of parents
  • Native language (what language was spoken at home)
  • Veteran status (children were asked if their father had been a veteran)
  • Social Security (whether you had a Social Security card)
  • Occupation and industry (your normal occupation and industry to track employment data)
  • Married women were asked if they had any previous marriages, their age at their first marriage and how many children did they have)

There were even some questions which were later rejected including "Do you own a Bible?" and "Are you over six feet tall?"

The 1940 U.S. Census also saw the use of many "codes" which the enumerator used to classify respondent information.

What? No 1940 U.S. Census Index?

Correct! There will be no initial index of the 1940 U.S. Census images. Why? Well, no one will have access to the images ahead of time, not even So no access means no way to index records. That is why you will need the tools below to help locate your family members on the images and why volunteering to help index the 132 million names is so important.

Finding 1940 U.S. Census Images

You will need both the address of family members on or around April 1, 1940 as well as the census enumeration district number for that address in order to locate the correct census image.

Step 1: Sources for 1940 Addresses and Locations

Something you can do prior to the April 2, 2012, release date is to determine the addresses of family members on April 1, 1940. Here are some places where you can look:

  • Family Members: Interview living relatives and ask if they remember where the family lived in 1940.
  • Address Books: Check to see if there are old address books available for your family.
  • Phone Books: Some libraries have archived copies of phone books available.
  • Vital Records: You may already have address information on birth, marriage and death certificates for your family members.
  • City and Business Directories: Look both online and a libraries for directories from 1939 and 1940.
  • Census Records: If you family did not move between 1930 and 1940, check for the address on the 1930 US Census or see if the state had an off-year census with address information.
  • World War II Draft Registration: Most of these records are from 1942 and beyond, starting two years after the 1940 US Census but the address information may be the same as the 1940 address.
  • Obituaries and Newspapers: Death notices, engagement and wedding announcements, and local news articles are good sources of address information.
  • Letters and Diaries: Look for address information on envelopes and letters; look for mentions of addresses in diary pages.
  • Passenger Lists and Naturalization Records: On a passenger list, look for an address for where the person would be staying. Immigration records should have a current address for the person applying for residency or citizenship.
  • Photographs: Look on the back of photographs for address information.
  • Organizational Yearbooks and Newsletters: Check for addresses in any fraternal organization materials or even workplace newsletters.
  • Yearbooks: Locate addresses for each graduating senior in yearbooks.

Step 2: Determine the Enumeration District

You will need more than just the address of your family members in 1940 - you will need to translate that location into the enumeration district number since that is how the 1940 US Census images are organized.

While having the 1930 US Census enumeration district will be useful, for many urban areas the enumeration district numbers changed between 1930 and 1940.

Step 3: Use the One-Step Tools

While you could pore over enumeration district maps and other materials, Steve Morse - of the One-Step Website fame - and his team have developed some handy online tools to help you locate the enumeration district for your family in 1940. See the information below on the various tools and how best to use them to locate enumeration district information.

What You Need To Know About Enumeration Districts

  • The 1930 US Census enumeration districts changed for the 1940 US Census, especially in the urban areas. There is a "conversion" tool on the One-Step site (see below).
  • It does make a difference if your family lived in an urban area (population over 50,000) or in a rural area.
  • You will be more likely to find the exact enumeration district number for family living in urban areas.
  • For rural areas, you may have to work with several enumeration districts or use the enumeration district maps to find the exact enumeration district.
  • Once you find the enumeration district, you may still have up to 80 or more page images to review.

One-Step Tools to the Rescue!

  • Take the Quiz: The easiest way to get started is to use an online tutorial in the form of a quiz at SteveMorse Quiz to help determine the best method and tool to determine the enumeration district.
  • Unified 1940 Census ED Finder: This tool will help you find an enumeration district for a specific 1940 location in one step: SteveMorse Enumeration District Finder .
  • Large City ED Finder: Use this tool if you already have a 1940 address for an urban area: Large City Finder.
  • ED Definition Tool: Use this tool if you already have a 1940 address for a rural area: ED DefinitionTool
  • 1930/1940 ED Conversion Tool: . ED Conversion
  • Census Tract Tool: Displays 1940 US Census tract maps for specific urban areas: Census Tract Tool.
  • Street Name-Change Tool: This tool helps determine street name changes in major cities: Street Name-Change Tool.
  • Census Image Tool: This tool will not be active until after the 1940 US Census images are released: Census Image Tool
  • Enumeration District Maps: For the first time, NARA has made ED maps for counties and urban areas available online. You can find them at Enumeration District Maps.

Other 1940 Census Information Sources

There are several others ways you can stay on top of the latest developments related to the 1940 US Census:

  • National Archives and Records Administration (NARA): there are various finding aids available at the NARA website at NARA.
  • One-Step Census FAQ: Steve Morse provides a comprehensive "frequently asked questions" page over at the One-Step site at One-Step Census.
  • The 1940 U.S. Census Community Project: visit Census Community Project for the latest news on the release of the 1940 US Census images as well as the volunteer indexing project. Also, check out the blog at Census Blog to help you put the 1940 US Census in historical context.


The release of the 1940 US Census images promises to be an important event for genealogists and family historians in the United States. With careful planning and gathering information about where your family members were living on or about April 1, 2012, you should be able to find the 1940 US Census images you need. Make sure you visit to follow all the developments related to the 1940 US Census images.

And don't forget that access to these images and the future index will be free thanks to the efforts of The 1940 U.S. Census Community Project, its partners (, FamilySearch and and the thousands of indexing volunteers. So do your part and learn more about becoming and indexing volunteer at

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