Basement Finishing Cost in Boston (2026)
Average cost in Boston
US$16,245 — US$81,225
US$50 — US$120 per sq ft
Cost Breakdown
ItemizedSkilled trades and general labor
40%
Drywall, flooring, and finishes
35%
Wiring, lighting, and rough-ins
15%
Moisture barriers and sump pumps
7%
City of Boston ISD fees and plans
3%
Sales Tax at 6.25%
📋What's Included
ScopeTypically Includes
- Framing & drywall
- Basic flooring (LVP or carpet)
- Electrical (outlets & lighting)
- Egress window (if required)
- Painting
- Basic bathroom rough-in
Typically Excludes
- Full basement bathroom
- Built-in bar or kitchen
- Home theater wiring
- Waterproofing (separate cost)
- Permits & inspections
Assumes an unfinished basement with existing concrete floor and basic utilities.
🧮Estimate Your Cost
InteractiveEstimated Cost
US$30,624 — US$45,936
Based on 8 sources and market data for Boston. Actual costs may vary depending on specific project requirements.
📈Price Momentum
Year-over-year~1 year ago
US$38,243
Today
US$40,385
Basement Finishing in Boston is ↑ 5.6% compared to roughly a year ago — about US$2,142 more on the average project.
Comparison derived from the year-over-year change rate, not a month-by-month price index. We don't store historical snapshots yet — when we do, this will become a real time series.
🏢Top Basement Finish Contractors in Boston
Verified providersFenway Masonry & Waterproofing, Chimney Repair, Basement Repair Boston
867 Boylston St Ste 501, Boston, MA 02116, USA
68 reviews
X'CLUSIVE RENOS & REMODELING LLC
17 Blakeville St, Boston, MA 02121, USA
42 reviews
Provider data sourced from public business directories. Ratings and reviews are public and may change. LookupCost is not affiliated with listed providers.
💬What People Actually Paid
Community❓Common Questions
Homeowners in the Greater Boston area can expect a return on investment (ROI) of approximately 65% to 75%, as finished basements significantly increase usable square footage in a high-density market.
Adding a full bathroom typically increases the project cost by $7,150 to $17,900, depending on whether a sewage ejector pump is required for below-grade drainage.
Yes, if the finished space includes a legal bedroom, Massachusetts state code requires an egress window. Installation in Boston's older foundations typically costs between $3,500 and $6,000.
The Boston Inspectional Services Department (ISD) typically requires a Long-Form permit for finishing unfinished space. Fees are generally $50 plus $10 per $1,000 of the estimated project cost.
📊Our Methodology
How we collect dataAggregated from 5+ verified web sources and cost databases
Licensed contractor estimates and regional cost guides
Government construction and labor statistics
Community-reported project costs and reviews
Last data collection: 3 days ago. Updates run weekly. All costs in USD.
About this data
Cost figures are estimates synthesized from public market data using AI research and refreshed regularly. Real project costs vary by scope, materials, contractor, and site conditions. Always get verified quotes from licensed contractors for your specific project.
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