Photograph: Sehjad Khoja on Pexels
Toronto permits up to four units on residential lots citywide, and up to six in detached buildings in Toronto and East York and in Ward 23 since June 2025. A free tool from the non profit ReHousing takes an address and shows what fits, with a rough budget, in a few minutes.
Most people still look at a Toronto lot and see one house. The zoning stopped saying that three years ago, and a free tool now makes it easy to find out what your own address allows.
How many units can you put on a Toronto lot?
Four, in every neighbourhood in the city. City Council adopted the multiplex study in May 2023, which amended the Official Plan and the citywide Zoning By-law so that low rise buildings of two to four units are allowed in all low rise neighbourhoods rather than only in a few of them.
That is the floor, not the ceiling. Garden suites and laneway suites are separate permissions that sit on top of it.
Where are six units allowed?
In two parts of the city, and only in a detached building. On 26 June 2025 City Council passed Official Plan Amendment 818 and Zoning By-law 654-2025, which permit fiveplexes and sixplexes in detached residential buildings across all low rise residential zones in the Toronto and East York Community Council area and in Ward 23, Scarborough North. The Toronto and East York area covers Wards 4, 9, 10, 11, 12, 13, 14 and 19, running from the rail corridor and Eglinton Avenue south to the lake, and from the Humber River east to Victoria Park Avenue.
The rest of the city is still at four. Council has directed staff to look at allowing up to six units and four storeys everywhere. Public consultation on that closed in April 2025 and no date has been set for a decision, so anyone planning around a citywide sixplex today is planning around something that does not exist yet.
What does the free tool actually do?
ReHousing is a non profit working with the University of Toronto's John H. Daniels Faculty of Architecture, Landscape and Design and with LGA Architectural Partners. Its Toronto site carries two tools.
The Quick Budget Tool takes two to three minutes. You enter the project type and the size and it returns a fast estimate of the main costs. The Property Analysis Tool takes six to ten minutes, checks what can be built on a specific property, and returns a more refined cost estimate.
The value is not the precision. It is that a homeowner can find out in ten minutes whether the idea is worth a conversation with an architect, instead of paying for that answer or never asking the question. The figures are ReHousing's own estimates. They are not a quote, not an appraisal, and not a substitute for a designer pricing your actual lot.
What about a garden suite or a laneway suite?
Both still stand, and both are citywide. Garden suites, which are small self contained homes in a back yard on a lot with no lane access, have been permitted across Toronto since February 2022. Laneway suites, on lots that back onto a lane, had their zoning standards updated in July 2025 to line up with Ontario Regulation 462/24.
What should you check before you count on it?
Zoning permission is not a building permit. What a by-law allows in principle and what a specific lot can carry are different questions, and the second one is decided by frontage, depth, height and setback limits, servicing capacity, heritage designation, and ravine and natural feature protection. A lot that looks identical to the one next door can answer differently.
The money side matters as much. Adding units is a construction project with a construction budget, a financing question and a timeline, and the return depends on what the finished units are worth or rent for rather than on how many of them the zoning permits.
If you are weighing this against simply moving, our affordability calculator and our selling page are the faster way to compare the two.
The honest summary is that Toronto quietly turned a large number of single family lots into small development sites, most owners have not noticed, and it now costs nothing but ten minutes to find out whether yours is one of them.
