Mississauga Building Permit Guide 2026

Mississauga charges a base permit fee plus a per-square-metre rate based on construction class. New single-family residential is rated at $14.85/m² gross floor area, additions at $14.85/m² of new floor area, and basement finishes at $9.80/m². Mississauga adds a 4% Building Code Act administrative fee on top of the base permit calculation. Missed inspection re-inspection fees are $165/visit; permit revisions during construction are $215 plus $14.85/m² for any added floor area.

Garden suite permits in Mississauga run roughly $1,050–$1,700 total for a typical 60–80 m² unit.

Mississauga Building Division requires a sealed drawing set from a BCIN-registered designer or P.Eng.

The standard package for an addition or new build includes:

• site plan showing setbacks, lot coverage, and building separation
• architectural drawings at 1:50 with floor plans, elevations, and sections
• structural drawings sealed by a P.Eng for any new beams, headers, footings, or load-bearing wall removal
• mechanical/HVAC layout with heat-loss/heat-gain calculations
• OBC Division 3 energy compliance package (updated under the 2024 Ontario Building Code)
• Ontario Building Code matrix
• Tree Inventory and Preservation Plan if any tree exceeds 30 cm DBH or your lot falls within a Treed area zone

Mississauga's ePermits portal (mississauga.ca/epermits) accepts digitally-sealed PDFs and processes payment online. The portal supports application status tracking and inspection booking, and most communications happen through the portal rather than by email.

1. Zoning compliance check: Mississauga's zoning by-law 0225-2007 governs setbacks, height, and lot coverage; book a free Pre-Application Meeting with Planning if your project tests any limits.
2. Submit application via ePermits: upload all sealed drawings, the Building Permit Application form, and zoning compliance information; pay 50% deposit on submission.
3. Plan review (8–14 business days): Building Division examiners review for OBC, zoning, and Site Plan Control compliance; large or complex projects over 500 m² may trigger SPC review separately.
4. Deficiency response: address any items from the deficiency letter and resubmit through the portal.
5. Permit issuance: pay the balance, download the permit card, and post it on site.
6. Construction inspections: book through the ePermits portal; a standard residential project requires 6–8 inspections from footings through final.
7. Final inspection and occupancy: required for new dwelling units before occupancy.

Mississauga's average first-review turnaround for 2026 has held at 8–14 business days for residential additions and basement finishes, and 12–18 business days for new builds. The City consistently meets or beats the Ontario Building Code Act statutory targets: 10 business days for houses and 15 for small buildings.

Garden suite permits typically issue in 6–10 business days because Mississauga aligned its Additional Residential Units by-law (0021-2024) with provincial Bill 23 and removed most discretionary review. Site Plan Control triggers, typically projects over 500 m² gross, add 6–12 weeks for the SPC review on top of the building permit clock.

Expect total time from complete application to permit in hand of 4–8 weeks for a typical addition, 3–5 weeks for a garden suite, and 8–16 weeks for a new build with no SPC trigger.

Mississauga's first-submission deficiency rate runs around 50%, better than Toronto's 60% but still high.

Top rejection reasons Konstruction Group sees:

1. zoning by-law 0225-2007 non-compliance, most often rear-yard setback at 7.5 m for additions
2. missing P.Eng seal on structural drawings
3. Tree Inventory and Preservation Plan missing for lots with mature trees
4. site plan dimensions not matching architectural drawings
5. missing OBC energy compliance package under the 2024 Ontario Building Code
6. Additional Residential Unit applications missing the Fire Safety Plan or fire separation details on shared walls
7. garden suite applications missing the rear-yard amenity space calculation.

Mississauga is stricter than Toronto on tree preservation. Trees on neighbouring lots within 6 m of construction require protection plans, and missing this remains a frequent cause of plan rejection.

Mississauga's permit-exempt work mirrors the Ontario Building Code general exemptions:

• like-for-like finish replacement (drywall, flooring, paint, cabinetry)
• window and door replacement in the same opening size
• minor plumbing fixture changes
• sheds under 15 m² with no plumbing or electrical
• decks at grade with no roof and no attachment
• fences under 2 m in residential rear yards

Mississauga-specific differences from Toronto: sheds are exempt up to 15 m² versus Toronto's 10 m²; pool fencing is exempt for fences at or above 1.2 m around pools, but the pool itself requires a separate Pool Enclosure Permit; masonry retaining walls are exempt under 600 mm in height. Driveway widening requires a separate Boulevard Permit even though no building permit applies. Electrical work requires ESA notification separately.

Confirm exempt status against Mississauga's Zoning By-law lookup before proceeding.