The Office of Policy and Management annually develops the full-value estimate of all taxable property within the 169 towns and cities. A ratio of assessment to market value is calculated from real estate sales occurring within each town and city. A separate ratio and full-value estimate is listed for four property types: residential, apartment, commercial/industrial/public utility and vacant land.

A list of municipalities and boroughs in Connecticut including municipality/borough code.

Submit the form on this page to nominate a dataset to be published on the CT Open Data Portal or the CT Geodata Portal.

The towns of Connecticut (CT) Parcels and Computer-Assisted Mass Appraisal (CAMA) data for 2022 are part of a zipped file containing two items: CT parcels in geodatabases organized by COGs and associated CAMA files.

The parcel information includes 169 out of 169 town organized with geodatabases for each of the 9 Council of Governments. Most of the parcel data sets can be linked to the CAMA data which has attribute information (e.g. value of house, number of bedrooms) about real property. The parcel features for each town are in shape files, feature classes, or within a geodatabase. Most parcels are organized by town and COG and placed within a geodatabases.

The CAMA data sets have information about real property within the towns of CT. It may be linked to the parcels using a join process within a GIS package like ArcGIS Pro or QGIS. 154 out of 169 towns have complete CAMA information. Of the remaining 15 towns, four have no information and the remaining have some limited information mixed into the parcel attribute tables. These files were gathered from the CT towns by the COGs and then submitted to CT OPM. Town data is organized by COG. Attribute names, primary key, secondary key, naming conventions, and file formats are not fully consistent but some cleaning and reorganization was conducted to improve quality. This file was created on 03/08/2023 from data collected in 2021-2022.

For administration of the American Rescue Plan (ARP), the Office of Policy and Management (OPM) is providing access to data on Qualified Census Tracts (QCTs) in Connecticut.
As part of guidance for implementation of the ARP, Treasury identified QCTs as "a common, readily-accessible, and geographically granular method of identifying communities with a large proportion of low-income residents. Using an existing measure may speed implementation and decrease administrative burden, while identifying areas of need at a highly-localized level."

This dataset contains information on individual properties owned by the State of Connecticut, which is collected and updated annually in March by the Office of Policy and Management. This inventory is maintained primarily for the purposes of payments in lieu of property taxes (PILOT) to the host municipality.

The column "Reference Number" refers to the unique ID for the parcel (if available) and the "Address" column contains the physical address when assigned by the municipality, otherwise the street name is provided.

This data is updated each March.

This dashboard provides data on allocated funds (allocations) and spending progress (expenditures) from the American Rescue Plan Act (ARPA) in Connecticut.

A listing of each of Connecticut's 169 municipalities indicating both the form of local government (such as Mayor-Council) and the Term in years for the Chief Elected Official

Updated annually as part of OPM's Municipal Fiscal Indicators report

This dataset includes information about state agencies publishing data on the CT Open Data Portal, including number of datasets, maps, external datasets (href), federated datasets (federated href), and data stories. It also includes a summary of the freshness of the data and the completeness of the metadata by agency.

A revaluation program is undertaken to secure a more equitable distribution of the tax burden, to bring the assessment level up to date, and to modernize assessment procedures. Furthermore, Connecticut law requires that all property be revalued for assessment purposes periodically. A revaluation is required to be completed every five years. The purpose of this requirement is to insure uniformity in real property valuations by eliminating inequities that may have developed since the previous revaluation.