Handout for “Hidden Clues in the U.S. Censuses" by Marilyn C. Toole
                                                                     October 13, 2016

United States censuses were taken every ten years from 1790 to 2010. Due to privacy concerns, a 72 year rule is in place for public viewing of the censuses, so the most recent one available is 1940. The 1950 census will be released April 1, 2020. The 1890 census was destroyed but searching on that search page brings up city directories, etc forward to +1960.


It is generally recommended that you begin with the 1940 census and work back. That way you can find your family and continue back in time to find their parents, and their parents, and so on.


Think of the censuses as a treasure trove of CLUES, not primary records. Census information is rife with errors, due to language differences, foreign accents, speech and hearing problems, poor handwriting and indexing errors. Only in the 1940 census do we know by an x by the name who in the household answered the enumerator’s questions.


Each census asks different questions. Some lead to other more accurate records such as marriage certificates, some do not. The records to look for from these hints include (for each family member) address, (look up house on google maps) variant spellings and nicknames, sex, color and race, exact birth date and place, marriage date and place, marriage status, number of marriages, place of birth of parents, number of children, relationship of each person in house to head of house, military service, deeds, business, agricultural and professional records, wife’s maiden name, movements around the country, relative wealth, proximity to other family members geographically, year of immigration and naturalization, trade or profession, education, language spoken, and foreign citizenship. Click here for information about the questions asked for each census year.


Since family relationships are not listed before 1880, other means must be found to establish kinship. Censuses before 1850 do not include other household members by name. There are podcasts and aids available by googling "finding aids for working with pre-1850 censuses" or going HERE.
As well as Federal decennial records, some states took censuses “on the fives” Check here for a list. Also taken were Agricultural, Veterans’, Manufacturing, Slaves, Mortality, Social Statistics. Not all have been digitized yet. 

Note the official census date for each census. Questions are answered according to what is happening on that date, not the date the enumerator visits the house.

You can find a list of the dates HERE.

Remember to try all possible spellings, search by first name only, browse township or ward.

                                                        Genealogy 101: What NOT to Do:

Forget that the censuses are just hints for your research

"Shotgun" Web Pages

Blindly follow someone else's "bread crumb" trail

Forget to follow every census record lead or Ancestry's hints

Avoid looking for names instead of records

Forget to follow siblings in other censuses forward

Neglect to use Soundex or Boolean search

Avoid "mowing the lawn"

Not use Ancestry's Trees

Be a "D" student on Documentation

Give up, but taking a break is fine.