Building Types | Fourplex

The Toronto Fourplex: Four Units, the City-Wide Maximum

Four units is the maximum permitted as-of-right anywhere in Toronto. Council adopted the multiplex by-law on May 10, 2023, permitting up to four units in residential Neighbourhoods zones city-wide. The City's own framing is that those four units fit roughly the same envelope as a detached house — no rezoning, no public meeting, and no parking required.

Key Takeaways

  • Four units is the city-wide ceiling — the as-of-right maximum everywhere.
  • Permitted in residential Neighbourhoods zones since the May 2023 by-law.
  • Fits roughly the same envelope as a detached house; FSI does not apply.
  • No rezoning, no public meeting, no parking for a compliant build.

Four Units, Roughly a House-Sized Envelope

The fourplex is the flagship form of Toronto's reforms because it is the most a lot can hold without leaving the as-of-right stream. The City's multiplex study permits up to four units within an envelope close to what a detached house on the same lot would occupy.

That envelope still has rules. The height overlay caps the building, the lot-coverage regulations still apply, and the setbacks are shared with other residential building types in the zone. The maximum FSI does not apply to a multiplex, which is why four units can fit without the floor-area constraint a house would otherwise carry. A design inside all of that goes to a building permit; one that exceeds it needs a minor variance.

Where the Fourplex Sits on the Ladder

Type Units Where allowed
Duplex 2 City-wide, as-of-right
Triplex 3 City-wide, as-of-right (also the Bill 23 floor)
Fourplex 4 City-wide, as-of-right (2023 multiplex by-law)
Sixplex 5–6 Nine wards as-of-right; opt-in elsewhere
Laneway suite +1 ancillary City-wide, on lots abutting a public lane
Garden suite +1 ancillary City-wide, on lots without a lane

Four units is the as-of-right ceiling everywhere; five or six are only permitted in nine wards.

No Parking Minimum

Since February 3, 2022, duplexes, triplexes, and fourplexes require no parking spaces in Toronto. For a fourplex this matters more than for a duplex: four parking pads would have eaten the rear yard and pushed the building footprint. Removing the minimum is a large part of why four units fit a house-sized envelope at all.

Best For

  • Getting the most units a lot can hold without leaving the as-of-right stream.
  • Residential Neighbourhoods lots where four units fit the height, coverage, and setback envelope.
  • Owners who want a building permit with no rezoning, no public meeting, and no parking.

Usually Fails When

  • Five or six units are assumed on a lot outside the nine sixplex wards.
  • The design exceeds the envelope and the Committee of Adjustment variance timeline was not planned.
  • A Heritage Conservation District adds review that was not scoped.

What To Verify Before Spending Money

  • The residential zone and Neighbourhoods designation for the parcel.
  • Whether the four-unit design fits the as-of-right envelope or needs a variance.
  • Whether the ward permits more than four units, if a fifth or sixth is wanted.

Where to Go Next

Frequently Asked Questions

How many units can a fourplex have in Toronto, and where? +
Four. Four units is the maximum permitted as-of-right anywhere in Toronto under the May 2023 multiplex by-law, in residential Neighbourhoods zones (RD, RS, RT). It is the city-wide ceiling — five or six units are only permitted in nine specific wards, not everywhere.
Do I need a rezoning or public meeting for a fourplex? +
No. The 2023 multiplex by-law made up to four units a permitted use in residential Neighbourhoods zones city-wide. Because the use is permitted, a compliant fourplex needs no rezoning, no Official Plan amendment, and no public meeting — it goes to a building permit.
Does a fourplex need parking in Toronto? +
No. Since February 3, 2022, duplexes, triplexes, and fourplexes require no parking spaces. Removing the minimum frees the lot area a parking pad or driveway would have taken, which is part of why four units fit roughly the same envelope as a detached house.
Does a fourplex really fit the same envelope as a house? +
Roughly, yes — that is the City's framing. Up to four units fit within an envelope close to what a detached house on the same lot would occupy. A fourplex lives inside the same as-of-right rules: the height overlay, the lot-coverage regulations that still apply, and the setbacks shared with other residential forms. FSI does not constrain a multiplex.
When does a fourplex need a Committee of Adjustment variance? +
When the design exceeds the as-of-right envelope — height, lot coverage, or setbacks. A design that stays inside them goes straight to a building permit. One that pushes past them needs a minor variance from the Committee of Adjustment, which adds time but is not a rezoning.
When did the four-unit by-law take effect? +
Council adopted the multiplex Official Plan and Zoning By-law amendments on May 10, 2023. The zoning amendment took effect May 12, 2023, and the Official Plan amendment took effect June 14, 2023, permitting up to four units across all Neighbourhoods-designated lands.

Official Sources Referenced

Screen Your Toronto Lot for a Multiplex

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