Across 67 permits filed since 2025-01-28, the median is $90,000; half of projects fall between $36,250 and $230,000. 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 New York County (Manhattan), NY actually reported when they pulled permits.
Recent filings
- Alt. GC filed interior demo and interior renovation on basement and first floor. demo existing stair and raised platform and replace with new. Add a new ADA platform lift. No change in use, egress and occupancy.Manhattan · 2026-07-20$262,020
- interior renovation replacement of sheetrock and finishes throughout. combination of two apartments at basement level as per TPPN #3/97Manhattan · 2026-07-06$476,000
- THIS APPLICATION IS FILED FOR IN CONJUNCTION GC APPLICATION TO ADD STRUCTURE INTO WORK TYPES TO LEGALIZE THE EXTENSION AT THE BASEMENT FLOOR AND TO ADDRESS VIOLATION# 39101132H ; NO CHANGE IN USE EGRESS OR OCCUPANCYManhattan · 2026-06-26$10,000
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 New York County (Manhattan), NY came in between $36,250 and $230,000. 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
Basement finishing in New YorkBasement finishing in ConnecticutBasement finishing on Long Island