Hartford, CT Accessory Structures: ADU Impact Fees (2026)

Connecticut municipalities derive their powers from the General Statutes, and the General Assembly has not enacted a development impact fee enabling statute. Connecticut courts have repeatedly held that municipal exactions on development must be tied to specific statutory authority (subdivision improvements under CGS Section 8-25, sewer connection charges under CGS Section 7-255, water connection charges under MDC charter authority) and cannot rest on general police powers alone. The result for an ADU project in Hartford is a fee structure made up of: (1) a zoning compliance review fee through the Planning Division (typically in the low hundreds of dollars depending on whether site-plan review is triggered); (2) building permit fees calculated on construction valuation under the Hartford fee schedule and the Connecticut State Building Code (CGS Section 29-263 authorizes municipal permit fees with a state education surcharge added); (3) separate electrical, plumbing, and mechanical permit fees; (4) plan review fees; (5) MDC water tap and sewer connection charges if a new service is installed (sharing the existing service with the principal dwelling avoids new connection charges); (6) Hartford Land Records recording fees if any easements or covenants are recorded against title. Connecticut requires a State Education Cost Sharing surcharge on building permits (CGS Section 29-263a, a small percentage of permit fees flowing to the state's school construction account), but this is not an 'impact fee' on the unit itself. School funding: Hartford Public Schools is funded through the state Education Cost Sharing formula and city general-fund appropriations; no school impact fee applies to new construction. Property taxes (Hartford's mill rate is among the highest in Connecticut due to a low residential assessment ratio and high commercial mill rate) on the increased assessed value after construction provide the long-term revenue stream.