Short answer: there is no single "garden suite loan" in Ontario. What exists is a stack: a provincial exemption from most municipal development charges on one ancillary unit, applied unevenly by the cities; a list of municipal fee refunds and cash grants that differ by city and expire on fixed dates; two federal tax measures that the Canada Revenue Agency's own pages say can reach a detached unit; one federal loan program that has been announced but, on the government's own pages, has not opened; and ordinary home financing that a mortgage professional, not a builder, should advise you on. This guide lists what is real as of 28 October 2026, with a source and a date for each. It does not tell you what you qualify for.
Who we are in this: a design-build company. We are not lenders, brokers, accountants or advisors, and nothing here is financial or tax advice. We publish this because the single most common question after "can I build one" is "is there any help paying for it," and the honest answer is "some, it depends on your city, and most of it has a deadline."
The one rule that applies everywhere: development charges
The Development Charges Act exempts one residential unit in an ancillary building on a lot with a detached, semi-detached or row house from development charges, and exempts additional units created in existing houses within limits (Development Charges Act s. 2(3.2)–(3.3)). On a new build, development charges can run to tens of thousands of dollars, so this is the largest single relief on this page, and it is provincial law rather than a program that can close.
Three cautions. Cities apply it through their own by-laws, and not all of them the same way. Toronto's By-law 845-2025 does not impose development charges on the second, third or fourth unit on a parcel of up to six (By-law 845-2025). Oakville relies on the Act's mandated exemption (Oakville development charges). Mississauga's ARU page says: "Development charges will also apply for additions and garden suites" (Mississauga additional residential units) — and the City's April 2026 incentives table marks second and third units "Exempt as per the Development Charges Act," without reconciling the two (Gentle Density Incentives Table). Budget for the charge in Mississauga and confirm in writing.
Education development charges are set by school boards and are not covered by the Act's exemption in every city: Brampton collects them before the permit is issued (Brampton garden suite process), Whitby states they apply to all detached ADUs (Whitby additional dwelling units), Oakville notes they "may apply to additional residential units that are exempt from Town and regional development charges" (Oakville page, above), and Burlington says they "may apply to detached Additional Residential Units" (Burlington ARU incentive program).
Where charges do apply, deferral may exist. Toronto can defer them for up to 20 years under a deferral agreement with a title restriction (Toronto DC deferral program), and Oshawa may defer residential charges to occupancy (Oshawa development charges).
Municipal money, city by city, with dates
Every program below is quoted from the city's own page, and every one of them can be changed by that city's council. Dates matter: two of these have already closed and two more close on a fixed day.
| City | What it is | Amount or scope | Condition | Status / deadline | Source |
|---|---|---|---|---|---|
| Mississauga | Building permit fee refund | "Building permit fees are refunded when you're building or legalizing ARUs," by cheque | After the ARU is constructed and inspected | Active (City ARU page) | Mississauga ARU page |
| Mississauga | New-address fee (a cost, not a credit) | "$81.90, plus HST, for a new address" for a garden suite | — | Active | Same page |
| Burlington | ARU Incentive Program — fee waivers and forgivable loans | — | — | Closed 1 October 2025; fee waivers ended 31 December 2025 | Burlington ARU incentive program |
| Whitby | Housing Accelerator Fund reimbursement | Building permit fee, ADU registration inspection fee, curb cut fee, below-grade entrance fee, and Education Development Charges for a detached ADU | Permit issued on or after 1 April 2024 | Register by 31 March 2027 or repay by 30 April 2027; "no exceptions or extensions"; minor-variance fees excluded | Whitby ADU page |
| Ajax | Cash grant per new unit | $2,000 for one unit; $3,000/unit for two (max $6,000); $4,000/unit for three (max $12,000) | Paid after permit issued, construction complete, permit closed | Active | Ajax ADU grants |
| Caledon | Gentle Density CIP — four streams | Grant A: up to $35,000 per property for a rural servicing review. Grant B: up to $50,000 per property for multiplexes. Grant C: up to $15,000 per unit for ARUs and multiplexes in new subdivisions. Grant D: up to $30,000 per unit for affordable rental ARUs, licensed, affordable for two years. | Permit issued on or after 25 November 2025; grants paid at permit issuance | Construction must begin before 31 December 2028; CIP in effect until 31 December 2028 | Caledon housing page |
| Brampton | Development Charge Reduction Program | 50% reduction of the City's portion of residential DCs; Region of Peel not reduced | Eligible types listed: single and semi-detached homes, townhouses, apartments. Garden suites and ARUs are not named on the program page. | 31 March 2026 – 30 March 2029 | Brampton DCRP |
| Brampton | Garden Suite Grant Program | — | — | Closed 21 July 2025 | Brampton garden suites |
| Toronto | DC exemption + deferral | Second–fourth units not charged; deferral up to 20 years where charges apply | Parcel of up to six units | Active | By-law 845-2025; deferral program (above) |
Richmond Hill, Oakville, Milton, Hamilton, Vaughan, Markham, Pickering and Oshawa state no fee rebate or grant on the pages we read; several charge registration fees instead (Whitby $268; Pickering a one-time fee under By-law 8040/23). Every figure is on GTA garden suite rules, city by city.
Federal measures
Three federal items touch a garden suite. Two are tax measures with live CRA pages; one is a loan program that has been announced three times and, as of the government's most recent page, has not opened.
The Canada Secondary Suite Loan Program — announced, not open. The 2024 Fall Economic Statement said the government "will double the loan limit for the Canada Secondary Suite Loan Program to $80,000," at "a low-interest rate of just 2 per cent" with "15-year loan terms" (Department of Finance, 10 December 2024). The federal housing programs index lists it under the heading "Canada Secondary Suite Loan Program — In development," with no amount, no eligibility rules and no application link (Housing, Infrastructure and Communities Canada, programs index, modified 12 November 2025). A September 2025 briefing said it "is expected to begin accepting applications in 2025-26" (transition binder). No official page states whether a detached unit qualifies, because no eligibility rules have been published. Our guide to the Canada Secondary Suite Loan Program must say the same: do not plan around it until a program page exists.
The Multigenerational Home Renovation Tax Credit — live, and the CRA says a separate structure counts. The credit is "14.5% of your costs, up to a maximum of $7,250, for each claim you are eligible to make," on "up to $50,000 in qualifying expenditures for each qualifying renovation that is completed" (CRA, line 45355, tax year 2025 page). A qualifying individual is "65 years of age or older at the end of the renovation period tax year" or "18 to 64 years of age and eligible for the disability tax credit"; only one renovation can be claimed for a qualifying individual in their lifetime. On the form of the unit, the CRA page is explicit: "You had renovation costs to create a secondary unit within the dwelling or on the property," and, under the heading "Building a separate structure as the secondary unit," "The secondary unit does not need to be physically part of an existing structure as long as it is on the same land as the eligible dwelling." The unit must be "newly constructed or created from an existing living space," have "a separate entrance, bedroom, bathroom and kitchen," and meet "applicable local requirements, permits, codes and by-laws"; the qualifying individual and relation must ordinarily inhabit the dwelling within 12 months after the renovation period (CRA, who can claim). Whether you qualify is a question for an accountant; see the Multigenerational Home Renovation Tax Credit.
The GST/HST new housing rebate — the CRA addresses laneway houses by name. CRA Info Sheet GI-168 treats a laneway house as "a separate, detached housing unit that is constructed on the same parcel of land as another residential complex," and says an owner-builder "may be eligible for a GST/HST new housing rebate if the laneway house is occupied as the primary place of residence" of the individual or a relation (CRA GI-168). Under the current guide, the federal rebate for an owner-built house is 36% of the GST paid to a maximum of $6,300 where the fair market value is $350,000 or less, phasing out to nothing at $450,000; the Ontario rebate is limited to $24,000 if you paid HST on the land and $16,080 if you did not (CRA RC4028, revised October 2026). An enhanced Ontario rebate applies to owner-built homes where construction begins on or after 1 April 2026, on a sliding scale by value (CRA Notice 346). If the unit is rented to a tenant rather than occupied by the owner or a relation, the new housing rebate is not available and a different rebate — the new residential rental property rebate — applies instead (CRA RC4231). Which rebate, and how much, depends on value, use and who occupies the unit; see the HST new housing rebate and ask an accountant before relying on any figure.
Ordinary home financing: what we will and will not say
Most garden suites are paid for the way most construction is paid for: from savings, a home equity line of credit, a mortgage refinance, or a construction loan. CMHC's own refinance product for secondary suites, for example, requires that "borrowers must own the home and they, or a close relative, must live in it" and that "the secondary suite must be self-contained and comply with applicable bylaws and regulations" (CMHC Refinance) — and does not say whether a detached unit qualifies. Those products have rates, terms and qualification rules that change monthly and depend entirely on you. We do not quote rates, we do not say what you qualify for, and we do not recommend a lender. The right person for that conversation is a mortgage professional, and the right time is after the feasibility check has told you whether the lot takes a suite at all — because a financing conversation about a building you cannot build is a wasted afternoon.
What we will do is give you the thing a lender needs from the builder's side: a scope, a sequence and a cost breakdown for your specific lot, labelled clearly as what it is. What a garden suite costs, and why we do not publish a price, is in what a garden suite costs in Ontario. A suite may legally be occupied by anyone under O. Reg. 299/19, including a tenant, subject to your city's registration or licensing rules; what it would earn is not a question this page, or this company, answers.
What we checked, and when
Every program on this page was read on the government's or the city's own page on 27–28 October 2026, and the page is cited beside it. Where a document could not be opened — Caledon's 2026 fees by-law, the federal loan program's non-existent program page — the gap is marked rather than filled from memory. Programs on this page have changed repeatedly this year: Brampton's grant closed in July 2025, Burlington's incentive program in October 2025 and its fee waivers in December 2025, Mississauga republished its incentive table in April 2026, Caledon's CIP opened in November 2025, and the CRA's MHRTC page now states 14.5% where its 2023 announcement said 15%. Treat the date at the top of this guide as part of the information, and if the official page and this one disagree, the official page wins and we would like to hear about it.
How to use this page
- Find your city in the table and on GTA garden suite rules, city by city, and write down the date on anything with a deadline.
- Confirm the development-charge position with the city in writing at pre-screening — the provincial exemption is real, but the city's own by-law and its education charges decide the final number, and Mississauga's page says the charge applies.
- Read the federal guide that applies to your situation, then confirm it with the CRA page it cites, and take it to an accountant.
- Take the lot check and the cost breakdown to a mortgage professional.
Disclaimer: Figures cited are market estimates provided for information only and are not a quote. Municipal rules, fees, and programs change — always verify current requirements with your local authority. Modular X provides exact pricing only after a site-specific feasibility review.