All of the federal census records for Connecticut are complete except for the 1890 census records. The Connecticut State Library holds microfilm or originals and indexes for each of those records.
There are also several records available through various Connecticut genealogical websites. The Connecticut State Library also has an index on file of a set of duplicate schedules for 1790-1850, which are located at the Connecticut State Archives.
That special set is not official and is not compiled in the same way as the official set, which means that it cannot be used to find a particular person. There is one key benefit of the special set, though. That benefit is that it doesn’t just list heads of households for 1850. Instead, it lists every member of each household.
Many different enumerations and population inventories for colonial Connecticut still exist today in various compilations. The Connecticut 1670 Census, for example, contains several freeman, probate, land, church and tax records.
It covers each of the colony’s heads of household from 1887 through 1673. However, it may not be entirely accurate, which means that it’s still important to cross-check that information against the source material.
The Grain Inventory for Windsor, Wethersfield and Hartford for 1669-1670 lists the bushels of corn and wheat in each family’s possession, as well as the number of people in the household and the name of the household’s head. The inventory doesn’t cover every single Connecticut resident, but it is an interesting and helpful genealogical record.
Age groups, races and sexes are listed in the 1756, 1762 and 1774 census records, but names are not.
State censuses were never taken for the state of Connecticut. However, the 1917 Military Census contained a list of all males between 20 and 30 years old in each town.
Some towns even extended that to the ages of 16 through 60. That same census listed nurses and other females with important occupations. Each person’s age, name, birthplace, occupation and dependents were listed. The census also noted whether or not a person was able bodied enough to do certain things.
Searchable Connecticut Census Databases
The Connecticut Census, 1790 – According to the official census performed by federal marshals in 1790, the population of Connecticut numbered 237,946. This index of households was provided by the federal government and is the most complete census for the state in the late 18th Century. Because it lists only the surname and given name of the head of the household, about 41,100 names are found in this database.
The Connecticut Census, 1790-1890 collection contains the following indexes: 1790 Federal Census Index; 1800 Federal Census Index; 1810 Federal Census Index; 1820 Federal Census Index; 1830 Federal Census Index; 1840 Federal Census Index; 1840 Pensioners List; 1850 Federal Census Index; 1860 Federal Census Index; 1890 Veterans Schedule; Early Census Index.
Connecticut, Military Census, 1917 – The Connecticut “Military Census” was taken in 1917–1918 at the direction of the General Assembly with an eye to assessing manpower available for war and other resources in the state. The census included surveys on agriculture, factories, and even automobiles, but the forms included here are questionnaires filled out by men ages 16 and over.