Across 247 permits filed since 2025-01-25, the median is $17,000; half of projects fall between $4,522 and $55,456. Figures are permit valuations reported to building departments. National cost guides answer this question with averages from other markets; these numbers are what homeowners in Hartford County, CT actually reported when they pulled permits.
Recent filings
- ***MIKE IS WORKING ON THIS**** Wiring for finish of basement with new lights, outlets, baseboard heaters, smoke and carbon detectors. Lights on 15 amp arc fault. Outlets on 20 amp arc and ground fault. Baseboard heaters on 240 volt 30 amp.Town of Southington · 2026-07-20$7,600
- ****DAVE IS WORKING ON THIS*************** Install an egress window and finish the existing basement to create a playroom/gym (approx. 580 sq ft). No bathroom and no sleeping area. C/A FeeTown of Southington · 2026-07-17$15,000
- ******JIM IS WORKING ON THIS***************** A finished basement (approx. 528 sq ft) to include a common area, children's play area, a half bathroom with plumbing installed above concrete, understairs storage and a small food prep area wiTown of Southington · 2026-07-17$60,000
How to read these numbers
Permit valuations are the project cost the applicant reports to the building department. They skew slightly low — nobody rounds up for the permit fee — and scope varies, so the middle-half range is the honest picture: half of all basement finishing permits in Hartford County, CT came in between $4,522 and $55,456. We exclude permits under $1,000, jobs filed as whole-house construction, and counties whose building departments don't reliably report valuations.
Same project, other places
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