Across 96 permits filed since 2025-01-25, the median is $150,000; half of projects fall between $38,750 and $1,100,000. 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 Greenwich, CT actually reported when they pulled permits.
Recent filings
- Finishing basement and adding a powder room.Town of Greenwich · 2026-07-07$40,000
- Partial basement finishing for a rec room & gym. No bedroom. Interior work only ELE: installation of wiring for a partially finished basement. 3 swtchs, 12 outlets, 9 fixtures (24 total devices)Town of Greenwich · 2026-07-02$43,000
- Partial basement finishing for family room & 1/2 bathroom, all interior work only.Town of Greenwich · 2026-07-02$67,471
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 Greenwich, CT came in between $38,750 and $1,100,000. 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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