Official provincial and municipal pages, pre-approved plans, market data, financing, and grants: the primary sources behind everything on this site.
Last reviewed: October 2026. Programs change; confirm with your municipality.
The statute permitting up to three units on most residential lots.
The bill's full legislative history and text.
Provincial guidance including minimum dwelling sizes.
Ontario's homeowner-facing overview of second units.
The code governing construction standards for all units.
Pre-approved plans; DC deferral.
Permit fee refunds and charge exemptions.
Up to three units; conservation approvals.
Caledon's housing and ADU portal.
Eligibility and parking rules; floodplain limits.
$246 registration; $260 fire inspection.
Up to three ARUs; municipal services required.
Mapping tool and CMHC catalogue designs; grant intake closed.
Five pre-approved detached designs.
Principal-residence and detached ADUs.
Up to three units; one may be in an accessory building (accessory buildings limited to 60 m² ground floor area in most zones).
Up to two ADUs urban; Greenbelt limits.
Up to three units per lot (principal home plus two ADUs).
ARU fee waivers ran until Dec 31, 2025, and the forgivable loan program closed Oct 1, 2025. Confirm current fees with the City.
Up to four units; $340 registration per ARU, renewed annually.
Dedicated ARU program.
Up to four units per lot.
Up to four units; no City DCs on the first two ARUs; ARU grant up to $20K–$30K while funds last.
One-time grant up to $10,000.
Up to 3 ADUs; $170 owner-occupied registration fee per new ADU.
Up to four units. London's 2026 ARU construction grants (up to $45,000 affordable / $20,000 standard) and permit-fee waiver are fully allocated and closed (permits issued Apr 29 to Sep 7, 2026). A repayable ARU loan remains available.
ADU/SDU and detached ADU guidance.
Up to two ADUs, urban and rural.
Up to two ARUs; DC exemption.
Up to three ADUs; DCs exempted.
Permit fee discount and rebate; design catalogue.
Coach house (laneway) and ADU rules.
ARUs strongly encouraged.
Speed approvals with city-vetted designs.
The City offers free pre-approved garden and laneway suite plans.
Five detached designs (with Whitby).
Design options to streamline permitting.
Insured refinance to fund a legal suite.
Broader CMHC financing programs.
Refinance up to 90% LTV / $2M to fund up to four suites.
Note: The proposed federal Canada Secondary Suite Loan Program never launched; Budget 2025 confirmed it will not be implemented.
One-time grant toward an additional unit.
London's 2026 ARU construction grants (up to $45,000 affordable / $20,000 standard) and permit-fee waiver are fully allocated and closed (permits issued Apr 29 to Sep 7, 2026). A repayable ARU loan remains available.
ARU fee waivers ran until Dec 31, 2025, and the forgivable loan program closed Oct 1, 2025. Confirm current fees with the City.
2nd/3rd ARU exempt from most municipal charges.
DC deferral for ancillary second units.
Financial support for eligible second units.
We translate these rules into a clear plan for your specific lot.
Talk to a feasibility expert