Ontario · six municipalities compared

Basement flooding subsidies in Ontario: six municipalities, and the rule that decides whether you get anything

Six Ontario municipalities will pay towards the devices that stop a basement flooding — a backwater valve, a sump pump, a battery backup, a disconnected downspout. The programme maximums run from $1,500 to $7,500, and that spread is not the interesting part.

The interesting part is that the programmes do not agree about the most basic question: whether you apply before the work or after it. Two of the six will not pay at all for work that has already started. Two others are built around claiming work you have already had done. Getting that backwards costs the whole grant.

This page is the comparison. Amounts read from each municipality's own page on September 21, 2026.

What each municipality calls it, and what it pays

Start here. The left column is the name you need to search or say on the phone — they are all different, and searching “basement flooding subsidy” in a city that calls it a grant programme finds nothing.

Why the headline maximum is not comparable between cities

Three of the six publish a share of your invoice as well as a dollar ceiling, and the shares are not close to each other: London pays 90% of total cost, Toronto 80 per cent, and the Region of Peel 60 per cent.

So a $2,000 invoice returns $1,800 in London, $1,600 in Toronto and $1,200 under the Peel rebate — before any of the dollar ceilings bind. A table of maximums alone will tell you Mississauga is the most generous. A table of maximums and shares tells you it depends entirely on what you are installing.

And the maximum is usually a ceiling, not a payment

Every one of these is “up to”. The amount that arrives is the lesser of the ceiling and the share of what you were actually invoiced. Ottawa states this most plainly of the six — the City rebates the lesser of the maximum amount or the cost of the work.

The rule that decides whether you get anything: before or after

This is the finding that made the page worth writing, and it is invisible if you only look at one city.

Apply first, build second — London and Windsor

Windsor states it as an instruction: “you must confirm eligibility and apply for the subsidy program before starting any work”.

The City adds that work performed by the homeowner, or completed before approval, is not eligible for a subsidy at all. Not reduced — not eligible. Windsor also requires the work to be done by a City-licensed plumber and to pass a final inspection, and approves applications on a first-come, first-served basis.

London puts the same rule the other way round, as an eligibility condition you must satisfy to apply: you must “have not commenced any construction of works related to the grant application”.

Build first, claim second — Toronto and Mississauga

Toronto runs on the opposite assumption. You apply within two years of installation, and the expanded amounts apply to work completed on or after 12 November 2025 with applications opening on May 1, 2026. A Toronto homeowner who waits for permission before starting has misread the programme in the other direction.

Peel is a third shape again: permit first, claim last

The Region of Peel sequences it in four steps and the permit comes before the valve: “apply for a building permit from your local municipality before installing”.

The rebate application is submitted only after the valve is installed and has passed a municipal building inspection. So the build can start — but only once a permit exists.

What to do with this if you are about to book somebody

One question, asked of your own municipality before you accept a quote: does your programme pay for work that has already started? It takes one call, the answer is binary, and it is worth between several hundred and several thousand dollars depending on where you live.

The conditions that disqualify people, by municipality

Every programme here has at least one condition that is not about the device at all. These are the ones that actually stop applications.

The condition Toronto applies that the others do not

Toronto requires downspouts to be disconnected from the sewer as a precondition of the subsidy, and separately states that “disconnecting the downspouts from your property’s eavestrough system is not eligible for a subsidy”. So it is required and unfunded in the same programme. Hamilton pays $75 + HST per downspout towards the same work and Mississauga pays $125 per downspout to a total of $500.

The condition that runs with the house

Toronto's caps are lifetime maximums per type of eligible work, attached to the property rather than to the owner, and Windsor's $3,500 is described the same way. Peel limits its rebate to one per residence every 10 years, and Mississauga excludes anyone who has had a sump pump rebate from the City in the last ten years.

If you have just bought, the question is not what you are entitled to. It is what the previous owner already claimed — and that is answerable by asking the municipality before you book anything.

Age and eligibility

Hamilton funds homes built before 1 January 2012, on the reasoning that backwater valves became mandatory in new sanitary construction from that year. London excludes homes in subdivisions registered after 1996, along with condominiums other than vacant land and non-residential properties. Both are drawing the same line: the money is aimed at the stock that was built without the protection.

Which device you actually need

The programmes fund several devices and they answer different failures. Claiming for the wrong one is a slower and more expensive mistake than missing a deadline.

The two are not substitutes, and the City of Toronto says why

Toronto's own split of the causes of basement flooding has two categories — stormwater or ground water seeping in, which is a drainage failure, and a sewer back-up caused by blocked, broken or overwhelmed lines. A sump pump answers the first. A backwater valve answers the second. A house can have either problem, or both, and no amount of the wrong device helps.

Which is why the single most useful item in any of these programmes is the one that costs least: Toronto funds a home plumbing assessment separately from the devices, and it is the only line item that tells you which of the others you need.

What none of them fund

None of these programmes pays for the damage. They pay for prevention. If water is already in the building, that is an insurance question, and in Canada it is a question with a surprising answer — the two ways water most often reaches a basement are both optional endorsements a standard policy leaves out. Twelve situations, and what the policy calls each one.

The cities with their own page on this site

Four of the six have a full page here, with the programme line by line, the conditions in order, and what the City publishes about its own sewers. The other two are covered above.

If your municipality is not on this list

Most Ontario municipalities of any size run something, and the ones here were read because they are the largest markets rather than because they are the only ones. The search term that finds it is usually the municipality's name plus one of: basement flooding subsidy, basement flooding grant, protective plumbing, backwater valve rebate, or private plumbing protection. If none of those returns a municipal page, the next question is whether your upper-tier region runs one instead — which is exactly how Peel works for Mississauga, Brampton and Caledon.

This site publishes nothing about a municipality it has not read directly. Where a figure is not here, it is because we have not opened that city's page, not because the programme does not exist.

The same comparison as a chart

Four of the six, drawn to scale. London and Windsor are not on it because the chart is generated from the four municipalities with pages on this site, and adding a bar for a city without a page would point nowhere.

Questions people actually ask

Where to read next

• Toronto, line by line
• Mississauga, and the second rebate from Peel
• Ottawa, and the by-law that set the amounts
• Hamilton, and the only published contractor prices
• What your policy does about the damage itself
• Which of the four kinds of basement flooding you have
• What the restoration work costs, and whose figures those are