Converting a Toronto basement into a legal rental apartment in 2026 takes 6–9 months from first call to first tenant, costs $75,000–180,000 all-in, and generates $1,800–2,600/month in rental income. Here’s exactly what the process looks like.

What “legal” means for a basement apartment in Toronto

Under Toronto Zoning Bylaw 569-2013, a legal second suite must have: its own exterior entrance (not through the main unit), minimum 1.95m ceiling height in habitable areas, fire separation from the upper unit (Type X drywall, fire-rated doors), egress windows in every bedroom, and registration with the City of Toronto.

An unregistered “income suite” that meets all these requirements is still technically legal to occupy but cannot be listed as a legal second suite — which affects your mortgage qualification (lenders discount unregistered rental income) and resale disclosure obligations.

Registration process for a second suite in Toronto

1. Get a building permit. Submit drawings (BCIN designer or architect) showing the suite layout, fire separation, egress, and entrance. Permit issuance: 8–14 weeks in 2026.
2. Build to OBC standards. Type X drywall between units, fire-rated door at top of staircase (if internal access exists), CO + smoke detectors hardwired and interconnected, separate laundry.
3. Pass all inspections. Frame, insulation, rough-in electrical (ESA), rough-in plumbing, and final occupancy.
4. Register with City of Toronto. File for second suite registration at the Building Division. Inspection confirms compliance. Certificate issued.

Ceiling height — the most common deal-breaker

Toronto OBC requires 1.95m (6’5″) minimum in living areas, 1.9m under beams. Most Toronto homes built before 1970 have 6’0″–6’2″ basements. Below threshold, your options are: bench footing (fastest, cheapest, loses 2–3 feet of floor space perimeter, $15–35K) or traditional underpinning (digs below existing footings, maintains full floor width, $300–600/linear foot, typically $45–80K for a typical semi).

Separate entrance options and costs

There are three standard approaches for a separate entrance in Toronto:

• Side-door with stairwell ($20–35K): New exterior opening cut through foundation wall, retaining wall if grade difference is significant, code-compliant staircase with railing.
• Walkout from backyard ($15–25K): Backyard grade allows a door at basement level. No major excavation needed. Most affordable if topography allows.
• English-style front or side entrance ($25–45K): Covered stairwell descending from sidewalk level to basement door. Common in older Toronto neighbourhoods (Leslieville, Parkdale, Riverdale).

What does a basement apartment conversion cost in Toronto in 2026?

Scenario	Estimated cost
Standard ceiling height, side-door entrance, 1 bedroom + 1 bath	$75,000–110,000
Standard ceiling height, walkout, 2 bedroom + 1 bath	$95,000–130,000
Low ceiling (underpinning needed), 1 bedroom + 1 bath	$130,000–165,000
Full build-out: 2 bedroom, 2 bath, full kitchen, separate entrance	$150,000–185,000

Rental income potential in Toronto 2026

Based on CMHC and Toronto Regional Real Estate Board data for 2026:

• 1-bedroom basement suite: $1,700–2,100/month
• 2-bedroom basement suite: $2,100–2,600/month
• Scarborough / North York average: $1,800–2,200/month
• East End / West End Toronto: $2,000–2,600/month

At $2,000/month with a $130,000 all-in conversion cost, payback period is approximately 5.5 years. Home equity increase on appraisal: typically $80,000–120,000 immediately post-registration.

Start with a free walkthrough

CNB has completed 137 basement projects across the GTA, including 43 legal second suite conversions. We handle permit, engineering, build, and registration coordination. Call (437) 217-5519 or request a free walkthrough — we come to you, assess the space, and give you a written quote within 24 hours.

Basement renovation in Toronto in 2026 costs $35–140 per square foot depending on scope. A 600 sqft basic finish runs $21,000–33,000. A legal second suite with separate entrance can reach $180,000. Here’s how to read those numbers.

What drives basement renovation cost in Toronto

Three variables move the needle more than anything else: ceiling height, plumbing configuration, and whether you need a permit for a structural change. Everything else — finishes, flooring, fixtures — is secondary.

Cost per scope in 2026

Scope	Cost range	What’s included
Basic open-concept finish	$35–55/sqft	Framing, insulation, drywall, flooring, pot lights, trim, paint. No plumbing.
Mid-tier with 3-pc bathroom	$55–80/sqft	Above + bathroom rough-in, vanity, toilet, shower, tile.
Legal second suite	$90–140/sqft	Full kitchen, bedroom, bathroom, laundry, egress windows, fire separation, permit.
+ Separate entrance	+$10,000–30,000	Side-door or walkout excavation, structural lintel, exterior door, stairs, railing.
Underpinning (low ceiling)	+$300–600/linear ft	Required when ceiling is under 1.95m. Bench or traditional underpinning.

The permit cost nobody tells you about

Toronto Building Permit fees for a basement renovation run $1,200–4,000 depending on the estimated construction value. You also need drawings — an BCIN designer charges $2,500–5,000, a P.Eng stamps structural at $1,500–3,000. Budget $4,000–8,000 for the admin work on a legal suite. Skipping the permit costs more when you sell.

Real project breakdown: 800 sqft legal suite, Etobicoke 2026

• Framing + insulation: $8,500
• Electrical (ESA permit included): $7,200
• Plumbing (2 full baths + kitchen rough-in): $11,400
• Drywall + tape + mud: $5,800
• Flooring (LVP throughout + tile in baths): $9,200
• Kitchen cabinets + countertop: $7,800
• Fixtures + hardware + trim: $6,100
• Separate entrance (side door + stairs): $21,000
• Permit + drawings: $5,400
• Total: $82,400

Monthly rent on this unit in Etobicoke 2026: $2,100–2,400. Payback period under 4 years.

What inflates the quote

Three things add cost that clients don’t always anticipate: asbestos (any home built before 1985 — abatement $2,000–8,000 if found), knob-and-tube wiring (must be removed from enclosed walls, $3,000–6,000), and waterproofing (if you have active water infiltration, interior weeping tile adds $8,000–15,000 before finishing).

How to get an accurate quote

An accurate basement quote requires a walkthrough — no contractor can give you a real number based on square footage alone without seeing ceiling height, existing mechanicals, and access. CNB offers free walkthroughs anywhere in the GTA. Call (437) 217-5519 or fill out the form below.