2024 Ontario Building Code in effect (harmonized with NBC 2020)
Ontario · 2024 Ontario Building Code, O. Reg. 163/24 under the Building Code Act, 1992
In force
Building codes
What changes
All law updatesThe new Ontario Building Code adopts the National Building Code 2020 with an Ontario Amendment Document, removing at least 1,730 technical variations. It took effect January 1, 2025. The 2012 code could be used until March 31, 2025 only where working drawings were substantially complete by December 31, 2024. All permit applications from April 1, 2025 must use the 2024 code.
- Law or regulation
- 2024 Ontario Building Code, O. Reg. 163/24 under the Building Code Act, 1992
- Jurisdiction
- Ontario
- In force
- Jan 1, 2025
- Official source
- Government of Ontario
Who it affects and how
Owners & developers
People and companies who own the property and commission the work, including homeowners renovating
Permits applied for from April 1, 2025 must show compliance with the 2024 code.
Contractors
General contractors, builders and construction business owners
Build to the NBC-based compendium, as Parts 3, 7 and 9 changed. Building Code exams switched to 2024 content on March 30, 2026.
Trades
Subcontractors and trade contractors
Part 9 and plumbing (Part 7) trades must follow the revised requirements.
Suppliers
Sellers of materials, products and equipment
Products and standards referenced by NBC 2020 now apply in Ontario.
Designers
Architects, engineers and designers
BCIN designers must design to the 2024 code and requalify with 2024 exams.
Not directly affected: homebuyers & customers, workers.
Plain-language summary by ArtBuild, checked against the official source on Oct 29, 2026. General information, not legal advice; you are responsible for how you use it. The official text governs: read it, and we recommend asking a lawyer or the regulator about your situation.