A Big Shift For Small Setbacks: Understanding Ontario's New 90% Rule

On November 21, 2025, O. Reg. 257/25 (the "Regulation") came into effect, allowing a setback to be treated as compliant if it's at least 90% of the setback required in the zoning by-law. While there are exceptions, in most cases proposed setbacks within 90% of the by-law standard will no longer require minor variance applications and committee of adjustment approval.

The Regulation

The Regulation is brief and prescribes the amount referenced in subsection 34 (1.4) of the Planning Act. For reference, subsections 34 (1.4) and (1.5) of the Planning Act were introduced by the Protect Ontario by Building Faster and Smarter Act, 2025 (Bill 17). Subsection 34 (1.4) provides that "[s]ubject to subsection (1.5), a minimum setback distance is deemed to be the prescribed percentage of the setback distance."

Subsection (1.5) provides that subsection (1.4) does not apply to a building or structure located:

a) in the Greenbelt Area within the meaning of the Greenbelt Act, 2005;

b) on a parcel of land that is not a parcel of urban residential land; or

c) on a parcel of land that includes any land in an area prescribed for the purposes of subsection 41 (1.2) of the Planning Act.

Subsection 41 (1.2) of the Planning Act provides for further exceptions and works together with O. Reg. 254/23. This regulation sets out the prescribed areas for the purposes of subsection 41 (1.2) (and, by extension, subsection 34 (1.5) (c)) of the Planning Act. As a result, the prescribed 90% minimum setback distance also does not apply to buildings or structures located in:

• Any area within 300 metres of a railway line, except:
• • A railway line to which the Canada Transportation Act applies and whose operations have been discontinued under section 146 of that Act,
  • An abandoned railway line to which the Canada Transportation Act does not apply, and
  • A railway line which is only used by an urban rail transit system.
• Any area within 120 metres of:
• • A wetland,
  • The shoreline of the Great Lakes-St. Lawrence River System,
  • An inland lake, or
  • A river or stream valley containing depressional features associated with a river or stream, whether or not it contains a watercourse.

Transition

These changes apply to existing and future applications. Pursuant to subsection 34 (1.6) of the Planning Act, despite any subsequent changes to a minimum setback distance though the Regulation, the minimum setback distance for a building or structure is deemed to be the minimum setback on: (a) the day a permit is issued under the Building Code Act; or (b) the day the lawful use of the building or structure was established in cases where no building permit was required. As a result, if you have an existing or planned minor variance application that includes setbacks, you may be able to eliminate the variance if you come within 90% of the zoning standard.

As always, Davies Howe LLP is here to keep you informed of new provincial legislation and how it will shape development across the province. If you have any questions or need guidance on these changes, our Land Use Planning Team is ready to assist.

Originally published November 27, 2025

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.