Basement Finishing Cost in London (2026)
Average cost in London
$30,000 — $150,000
$40 — $200 per sq ft
Cost Breakdown
ItemizedDrywall, flooring, lumber, and fixtures
45%
Framing, electrical, plumbing, and finishing
35%
City fees and architectural drawings
10%
Buffer for unforeseen repairs or moisture issues
10%
HST at 13%
📋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
$26,340 — $39,510
Based on 12 sources and market data for London. Actual costs may vary depending on specific project requirements.
📈Price Momentum
Year-over-year~1 year ago
$50,120
Today
$52,926
Basement Finishing in London is ↑ 5.6% compared to roughly a year ago — about $2,807 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 London
Verified providersGold Level Contracting
288 Grangeover Ave, London, ON N6G 4K5, Canada
54 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
In 2026, standard basement finishing costs between $40 and $85 per sq ft. However, converting a space into a legal secondary suite typically costs between $120 and $200 per sq ft due to strict building code requirements.
Yes, the City of London offers Additional Residential Unit (ARU) grants of up to $45,000 for homeowners creating legal secondary suites. Additionally, the city has periodically waived building permit fees for such projects to encourage housing density.
According to the Ontario Building Code (OBC) applied in London, a legal basement apartment must have a minimum ceiling height of 6'5" (1.95m) over at least 75% of the required floor area.
Adding a new 3-piece bathroom typically costs between $8,000 and $25,000, depending on the proximity to existing plumbing stacks and whether concrete must be broken for new drainage lines.
Permit fees for a standard basement finish generally range from $1,000 to $3,000, covering plan reviews and multiple inspections. Fees may be higher for legal suites that require development charges or specialized HVAC and electrical permits.
📊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: 1 weeks ago. Updates run weekly. All costs in CAD.
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.
Spotted bad data? Let us know — we'll review and update.