Policy & Zoning | Bill 23
Bill 23 and Ontario's Three-Unit Rule
Bill 23, the More Homes Built Faster Act, 2022, is the Ontario law that requires every municipality to permit up to three residential units on most lots as-of-right — no rezoning. It is the floor every Ottawa multiplex project starts from, before the City's own by-law adds more.
The Three-Unit Floor
Bill 23 guarantees three units on a residential lot anywhere in Ontario. It can be arranged in three ways:
Three units in the primary building
A house converted or built as a triplex — three self-contained units under one roof.
Two units in the primary building + one ancillary
A duplex plus a garden suite or laneway home in the rear yard.
One unit + two ancillary (where serviced)
A house plus a coach-house arrangement, subject to local servicing and lot rules.
Source: Province of Ontario — More Homes Built Faster Act, 2022.
Floor, Not Ceiling
The key thing to understand about Bill 23 in Ottawa: it is a minimum. A municipality cannot allow fewer than three units, but nothing stops it from allowing more. Ottawa used that headroom. Its Zoning By-law 2026-50 sets a four-unit as-of-right baseline and permits more in the higher N-zones. So in Ottawa, the City rule governs day to day — but Bill 23 is the backstop that guarantees the province can't let a municipality drop below three.
What Else Bill 23 Did
Beyond the three-unit rule, Bill 23 removed parking minimums for residential development near major transit stations, exempted the additional residential units from development charges in defined cases, and limited the scope of municipal site-plan control for small projects. These changes were designed to make the small multiplex cheaper and faster to approve. Read the full bill text for the precise provisions, which have been amended several times since 2022.
Best For
- ✓ Understanding the province-wide three-unit floor that applies under every Ottawa lot.
- ✓ Seeing how a triplex or duplex-plus-garden-suite qualifies as-of-right anywhere in Ontario.
- ✓ Knowing why Ottawa can — and does — allow more than Bill 23 requires.
Usually Fails When
- ✕ You assume Bill 23 is the operative rule in Ottawa — the City by-law allows more and governs day to day.
- ✕ You treat Bill 23 as a guaranteed fourth unit — the provincial floor is three.
What To Verify Before Spending Money
- → The current Bill 23 text on ola.org, since it has been amended since 2022.
- → Whether your project relies on the provincial floor or on Ottawa By-law 2026-50, which is more generous.
- → Whether your additional units qualify for the development-charge exemptions.
Frequently Asked Questions
What is Bill 23 in Ontario?
How many units does Bill 23 allow as-of-right?
Does Bill 23 override Ottawa's zoning?
Did Bill 23 remove parking minimums?
Official Sources Referenced
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