Our Population Statistics Overview provides detailed information about each of the population data sources available for Connecticut, limitations of and differences between the datasets, and Q & A examples which may help when choosing a data source. The US Census Bureau's population estimates terms and definitions may also be helpful.
Annual July 1 Estimates
The Connecticut state, county and town level populations are estimated at the calendar year midpoint (July 1) each year. These July 1 estimates typically constitute the basis for determining birth, death, and other population based rates. The annual estimate represents the official Connecticut population estimate for the year.
Decennial Census Population Counts
The US Census Bureau takes a census of the population of the United States every 10 years which is known as the decennial census. A major source of population data for CT, the decennial census attempts to provide a true count of the population rather than an estimate. The decennial census serves as the population base for the next 9 years of annual estimates. To access Census data for Connecticut geographies, please visit Connecticut State Data Center or the US Census Bureau.
The Census 2020 collected population counts and demographic characteristics of the Nation and its component geographies as of April 1, 2020. Data are expected to be released in late May 2023.
The Census 2010 collected population counts and demographic characteristics of the Nation and its component geographies as of April 1, 2010. Census 2010 marks the first decennial census that does not use a long form to collect social and economic data.
Other US Census Products
In addition to the decennial census, the U.S. Census Bureau also releases several other data products that provide detailed social, demographic, and economic data.
American Community Survey — annually: The American Community Survey (ACS) is an ongoing survey that provides data every year - giving communities the current information they need to plan investments and services. Information from the survey generates data that help determine how more than $675 billion in federal and state funds are distributed each year.
Economic Census — every 5 years: The economic census provides a detailed portrait of the United States' economy once every five years, from the national to the local level. Government agencies, businesses, entrepreneurs, researchers and others use economic data to develop public policy, evaluate industry growth, plan disaster relief services, assist local businesses and much more.
Census of Governments — every 5 years: The Census of Governments provides data about how governments are organized, how many people they employ and payroll amounts, and the finances of governments. Federal statistical agencies use the data to measure the nation's economic and financial performance. State and local governments use the data to develop programs and budgets, assess financial conditions, and perform comparative analyses. Analysts, economists, market specialists, and researchers use these data to measure the changing characteristics of the government sector of the economy and to conduct public policy research.
Demographic, Economic and Other Surveys — A survey is a method of collecting and analyzing social, economic, and geographic data. Throughout the decade between censuses we are continually conducting surveys to produce a general view and comprehensive study of the United States' social and economic conditions. For more information, visit www.census.gov.
Economic Indicators — Economic indicators released by the Census Bureau include data on manufacturing, retail and food service sales, housing vacancies and ownership and international trade. View the economic indicator release schedule.