Secondary Suite Permit Process Ontario - What to Expect in 2026

After Bill 23 and the provincial zoning changes, adding a secondary suite has become more straightforward in Ontario - but it is still not simple. I navigated the Toronto process last year, here is what I learned.

The Short Version

Ontario now requires municipalities to permit at least 3 units per residential lot. This means your municipality cannot refuse a secondary suite application just because of zoning - but they can and will enforce the Ontario Building Code requirements strictly.

Permits You Need

  • Building permit (mandatory for all secondary suite work)
  • Electrical permit (separate panel/sub-panel for the suite)
  • Plumbing permit (if adding kitchen or bathroom)
  • HVAC permit (if modifying mechanical)

Toronto also requires a zoning review. Budget $2,000-$5,000 just for permit fees depending on scope.

OBC Requirements for Basement Suites

  • Minimum ceiling height: 1.95m (6’5")
  • Egress window meeting minimum dimensions (approximately 0.35m2 clear opening)
  • 1-hour fire separation between units
  • Interconnected smoke + CO alarms in both units
  • Separate HVAC or air handling that prevents cross-contamination

Real Cost in Toronto

Converting an unfinished basement to a legal 1-bed suite: $75,000-$110,000 including permits, egress window, separate entrance, waterproofing, electrical sub-panel, kitchen rough-in and finish, bathroom, and flooring. Do not underestimate the scope.

Income Potential

Legal Toronto basement suite: $1,800-$2,500/month. Payback on conversion cost typically 5-7 years. Significant resale value add.

Has anyone recently done this in 905? Curious if the permit process is faster outside Toronto.