These projections are created based upon several datasets and while these estimates are developed based on multiple data sources, actual population changes may vary from these projections. To assist in planning, analysis, and decision making, the population projections have been developed based on state and locally derived fertility rates.

The 2015 to 2040 population projections for towns in the state of Connecticut were developed by the Connecticut State Data Center for planning, analysis, and to inform decision making. The projections are individual population projections for the resident population of each of Connecticut's 169 towns and were published on August 31, 2017. These projections supersede the 2012 edition of the population projections developed by the Connecticut State Data Center.

The 2015 to 2040 population projections for the state of Connecticut were developed by the Connecticut State Data Center for planning, analysis, and to inform decision making. The projections are individual population projections for the resident population of Connecticut and were developed on July 31, 2017 and revised and republished on September 19, 2017 to address an error in the original dataset that was published on July 31, 2017. The County and Regional Council of Government Projections were published on June 29, 2018 and are based on the projections developed on September 19, 2017. These projections supersede the 2012 edition of the population projections developed by the Connecticut State Data Center.