The Mississauga Stormwater Charge,
Decoded
It shows up on your Peel Region water bill, not your property tax bill, and almost nobody remembers agreeing to it. Here's what it costs in 2026, how your tier gets decided, and what you can actually do about it.
In this article
If you own a home in Mississauga, you're paying between $64.45 and $219.13 a year for stormwater. It's on your Region of Peel water bill. It's not on your property tax bill, and that's the single thing most people get wrong about it.
It's not a mistake, it's not a Peel Region fee, and you can't opt out of it. It's a City of Mississauga charge that Peel collects for the City, because Peel is already sending you a bill anyway. So there's no point fighting the charge itself. What you can do is check whether the City put you in the right tier, because your tier comes from an aerial photo of your roof, and aerial photos are not always right.
Five residential tiers, set by rooftop area. Most detached homes in Mississauga land in the middle tier at $128.90 a year. It's billed daily, so it shows up as roughly $32 on a typical quarterly water bill. If you think your tier is wrong, the review is free and you can start it online.
What the Stormwater Charge Costs in 2026
There are five residential tiers. Your tier is set by your rooftop area in square metres, and nothing else on the residential side. Here's the full table, with what the same tier cost last year so you can see the increase.
| Tier | Typical property | Rooftop area | 2025 | 2026 | Change |
|---|---|---|---|---|---|
| Smallest | Freehold townhomes and row houses | 26.7 – 99 m² | $61.95 | $64.45 | +$2.50 |
| Small | Semi-detached and linked homes | 99.1 – 151 m² | $86.73 | $90.23 | +$3.50 |
| Medium | Medium single detached | 151.1 – 194 m² | $123.90 | $128.90 | +$5.00 |
| Large | Large single detached | 194.1 – 242 m² | $148.68 | $154.68 | +$6.00 |
| Largest | Very large single detached | 242.1 m² and up | $210.63 | $219.13 | +$8.50 |
Every tier went up by the same 4.04% this year. The dollar increase looks different across the table — $2.50 at the bottom and $8.50 at the top — but that's only because the tiers are multiples of each other. Nobody got singled out.
What it actually looks like on a quarterly bill
The City doesn't charge you the annual figure in one lump. Your annual charge gets divided into a daily rate, and Peel bills you for the number of days in your billing period. So the amount moves a little from bill to bill depending on how many days that bill covers.
| Tier | Per day | Per 91-day quarter | Per year |
|---|---|---|---|
| Smallest | $0.18 | $16.07 | $64.45 |
| Small | $0.25 | $22.50 | $90.23 |
| Medium | $0.35 | $32.14 | $128.90 |
| Large | $0.42 | $38.56 | $154.68 |
| Largest | $0.60 | $54.63 | $219.13 |
Daily and quarterly figures are the annual charge divided out — $128.90 ÷ 365 is 35 cents a day, and 91 days of that is $32.14. Your bill period probably isn't exactly 91 days, so treat the middle column as close, not exact.
On a typical Mississauga water bill, the service delivery charge alone is $81.24 a quarter for a 5/8" or 3/4" meter. The stormwater line on a mid-tier detached home is about $32 on top of that. It's the smallest line on the bill, and it's the only line the Region of Peel doesn't actually control. For the rest of the bill, see Your Peel Region Water Bill, Decoded.
Everything Is a Multiple of 267 Square Metres
Here's the thing that makes the whole system click once you see it. The City picked one reference property and priced everything off it. That reference is 267 square metres of hard surface, which the City says is the average hard surface area on a single detached residential property in Mississauga. That's one billing unit.
The 2026 rate is $128.90 per billing unit per year. In 2025 it was $123.90. That's the only number Council actually votes on. Every tier price on the table above is that rate multiplied by a fixed number of billing units.
Freehold townhomes and row houses. Half a billing unit, half the standard charge.
Semi-detached and linked homes. Seven tenths of a unit.
The baseline. A medium single detached home is the property the whole system is priced against.
Large single detached. Twenty per cent more than the baseline home.
Very large single detached. The top of the residential scale at 1.7 units.
The City publishes the tier dollar figures and not the multipliers, but I ran the arithmetic and the multipliers fall straight out of it. $123.90 Ă— 0.5 is $61.95, and $128.90 Ă— 0.5 is $64.45. Same for 0.7, 1.2 and 1.7, to the cent, in both 2025 and 2026. So if Council raises the rate again next spring, you don't have to wait for the City to publish a new table. Take the new per-unit rate, multiply it by your tier's number, and you have your own figure.
Why This Is On Your Water Bill and Not Your Property Tax Bill
This is the part that confuses people, and the confusion is reasonable. The stormwater system is a City of Mississauga asset. The City sends you a property tax bill. So why is the charge for a City asset riding on a Region of Peel water bill?
Because it's not a tax. It's a user-pay charge based on how much hard surface sits on your property, and hard surface is what generates runoff. Property tax is based on your assessed value, and assessed value tells you nothing about runoff. A $2 million house on a small lot with a modest roof can shed less water than a low-value commercial building sitting behind an acre of asphalt. Charging by assessed value would have billed those two backwards.
So the City set it up as a charge on every property that drains into the City's stormwater system, and put it where the utility bill already goes. Peel Region collects it on behalf of the City of Mississauga. Peel doesn't set it, and Peel doesn't keep it. If you call Peel to complain about it, you're calling the wrong number.
You still pay. Peel Region issues either a water bill or a stormwater-only bill on behalf of the City to every property owner the charge applies to. Having no water account doesn't exempt a property that drains into the system.
Where the charge came from
Council approved it on May 27, 2015, after a two-year Stormwater Financing Study that took input from a stakeholder group of roughly 30 residents, commercial representatives and conservation authorities. It's been in place since 2016, and Mississauga was the first city in the GTA to bring one in. Before that, stormwater came out of property taxes and reserves, which is exactly why it feels like something you never agreed to. You didn't agree to it. Council did, eleven years ago.
What it pays for is long-term planning and new capital construction — replacing aging stormwater infrastructure — plus the day-to-day operations and repairs that keep the existing pipes, ponds and outfalls working. It's a dedicated fund, which means it can't be quietly moved to something else the way a tax-supported budget line can. I'll say plainly that this is the part I actually like. Money you pay for pipes goes to pipes. Compare that to your property tax bill, where everything lands in one pot and you have no idea which line paid for what. I'd rather pay a fee I can trace than a tax I can't.
How Your Tier Gets Decided
Residential tiers are set by rooftop area. Not lot size. Not driveway. Not frontage. Not how many cars you park. Just the footprint of your roof, measured from the air.
That surprises people, because your driveway is obviously hard surface and it obviously sheds water. It counts in spirit, just not directly. The City uses rooftop area as what it calls a reliable predictor of the total hard surface area on a residential property. Bigger roof, bigger house, bigger driveway, bigger patio, on average. Rather than measure four separate surfaces on 150,000 homes, the City measures one and infers the rest.
The measurement itself comes from aerial imagery. The City uses software that looks at your building from multiple angles to work out the hard surface area. But the coloured overlay you see in the online estimator doesn't always line up with the photo underneath, because those photos were shot from a plane at an angle. That's the soft spot in the whole system. It's also the only soft spot you can do anything about, which is why the rest of this article keeps sending you back to that overlay.
The review process doesn't look at soil type, the ratio of building to lot, how close you are to a creek or the lake, or whether you have private stormwater measures on site. A rain barrel and a permeable driveway won't move a residential property down a tier. Only the mapped area does that.
🧮 Stormwater Tier Checker
This checker applies the City's published tier boundaries to a footprint you supply. It's not the City's assessment of your property. For the number the City actually has on file, use the official stormwater estimator at estimator.stormwatercharge.ca — type in your address and it shows your daily and annual charge along with the aerial image and the coloured overlay used to assess you. Look at the overlay. That's the whole case if you decide to ask for a review.
Why Your Neighbour on the Same Street Pays Less Than You
Two houses that look identical from the sidewalk can sit in different tiers, and the gap isn't small. This is the most common reason people go looking for an explanation in the first place.
The tiers are cliffs. The Medium tier ends at 194 m². The Large tier starts at 194.1 m². A roof measured at 194 m² pays $128.90 a year. A roof measured at 194.5 m² pays $154.68. That's $25.78 a year for half a square metre — about the size of a bar fridge lid. There's no gradual slope between the tiers, no partial credit for being barely over. You're on one side of the line or you're on the other.
So the honest answers to why your neighbour pays less are usually one of these:
Same street, same era, different builder plan. A 190 m² footprint and a 200 m² footprint are hard to tell apart from the road, and they sit in different tiers. That's $25.78 a year, and it's correct.
A rear addition, a garage extension, a covered porch, a sunroom. Anything with a roof over it adds to the mapped rooftop area. The City maps from the most recent aerial imagery, so a roof that grew eventually shows up in the assessment.
Semi-detached and linked homes sit in the Small tier at 0.7 billing units. A detached home next door in the Medium tier is at 1.0. That's $90.23 against $128.90, a $38.67 a year difference on two houses sharing a property line.
This is the one worth acting on. Aerial mapping picks up a shed, a gazebo, or a neighbour's overhanging roofline and attributes it to you. If your overlay in the estimator covers something that isn't yours, or covers a structure you took down years ago, request a review.
Condos, Townhouses and Businesses Are Charged Differently
The five-tier table only applies to residential properties. Everything else — commercial, industrial, institutional, and multi-residential buildings — is measured directly and charged on the actual number.
The formula is simple. Total hard surface on the site, divided by one billing unit of 267 m², multiplied by the current rate of $128.90. So a site with 8,000 m² of hard surface works out to 29.96 billing units, which is $3,862 a year. No tiers, no rounding into brackets, just the measured area.
Why condo owners never see a stormwater line
A building owned and operated by a condominium corporation gets one assessment for the whole property. The City doesn't bill the 400 individual unit owners. The condominium board or the property manager decides how the charge gets divided among the owners, and the board or the property manager handles collecting it.
Which means it reaches you through the common expense budget your maintenance fee funds. There's no line on any statement that says stormwater. So if you own a condo and you've been hunting for this charge on your water bill, that's why you can't find it. You're already paying it. It's just buried in your fees. For what else is buried in those fees and what a normal number looks like, see Square One Condo Fees: What's Normal and What's a Red Flag.
If you own a freehold townhouse or row house, you're residential, not multi-residential. You're in the Smallest tier at $64.45 a year, and it shows up on your own Peel water bill as its own line. The condo treatment above applies to condominium corporations, not to freehold towns.
Can You Get It Removed or Reduced?
Let me be blunt here, because I'd rather save you the phone call. You can't get the stormwater charge removed. Every property that drains into the City's system is charged, and there's no opt-out. What does exist is a subsidy for a narrow group of residents, a free review if the measurement is wrong, and a credit program homeowners are shut out of.
1. The subsidy for low-income seniors and persons with disabilities
If you qualify for the City of Mississauga's tax rebate program for low-income seniors and low-income persons with disabilities, you automatically qualify for the stormwater charge subsidy. There's no separate application. Qualify for the rebate and the subsidy follows.
To qualify for the underlying rebate you need to be at least 65 years old or have a disability, own and live in your own home for at least one year, and every owner of the property has to be receiving Guaranteed Income Supplement (GIS) or Ontario Disability Support Program (ODSP) benefits, or be the spouse of an owner who is. GIS recipients need to supply the previous year's T4A(OAS) slip.
How the subsidy reaches you depends on what you own. For a single-family home it's credited to your Region of Peel water bill. For a condominium the City mails you a cheque, because the charge went to the corporation rather than to you.
The rebate isn't automatic year to year. You have to apply every single year, and the deadline is December 31. The City doesn't accept backdated applications, so a missed deadline is a missed year. Full stop. Apply by email to [email protected] or in person at 300 City Centre Drive. The City doesn't publish the subsidy amount on its rebate page, so confirm what it works out to for your property by calling 311.
2. Request a review of your assessment
If you think the hard surface on your property was measured incorrectly, you can ask for a review, and it costs nothing. The review checks whether your rooftop or impervious area was mapped accurately against the most recent aerial imagery. Start it online at the stormwater estimator with your address and email, or download the Request for Review Form and send it to [email protected], fax it to 905-615-3405, or mail it to Environmental Services, Transportation and Works, 300 City Centre Drive, Mississauga, ON L5B 3C9.
Two things to know before you file. Site visits aren't part of the review. Nobody comes out to look, it's all done from the imagery. And the review can go either way. In the City's own words, requesting a review doesn't guarantee your charge will be lowered, and the charge may be raised, lowered or unchanged. So look at the overlay on the estimator first, and I mean actually look at it. If it matches your roof, leave it alone. A review you didn't need can cost you money.
3. The credit program — and why it isn't for you
There's a stormwater credit program that can cut the charge by up to 50%. Single residential properties are not eligible. It's for businesses and multi-residential properties only. No amount of rain barrels, permeable pavers or downspout disconnection will reduce a house's stormwater charge, and I'd rather you hear that from me now than find it out after you've spent a weekend and a few hundred dollars on it.
If you do own commercial, industrial or multi-residential property, the credit is worth real money, and it stacks across four categories:
| Credit category | What it covers | Max credit |
|---|---|---|
| Peak flow reduction | Controlling runoff rates through drainage controls, chambers or basins | 40% |
| Water quality treatment | Removing contaminants via ponds or green infrastructure | 30% |
| Runoff volume reduction | Capturing rainfall through bioretention or permeable surfaces | 30% |
| Operations and activities | Sustainable landscaping, employee education, pollution prevention | 20% |
| Total credit cap for a single property | 50% | |
The categories add up to 120% on paper but the cap is 50%, so hitting two categories well is usually enough. Applications need engineering reports prepared by a Professional Engineer registered in Ontario, processing takes a minimum of four to six weeks, and the City may inspect the site before approving. Credits run for up to five years, and they expire if you don't renew before the expiry date. Put the renewal date in a calendar the day the credit is approved. An expired credit is the easiest 50% anyone ever loses.
Your Checklist
Look for the stormwater charge, separate from water and wastewater. Check it against the tier table above. If you own a condo, stop here — yours is inside your maintenance fee and there's nothing to find.
Go to estimator.stormwatercharge.ca and enter your address. It gives you the daily and annual charge the City has on file, plus the aerial image and coloured overlay behind it.
Does the shaded area match your actual roof? Does it include a structure you tore down, a neighbour's overhang, or a shed that isn't yours? That's your evidence, and it's the only kind that matters here.
Start it from the estimator with your address and email, or send the Request for Review Form to [email protected]. It's free. But remember the charge can go up as well as down, so only file if the mapping is genuinely wrong.
The stormwater subsidy comes with it automatically and there's no separate form. Email [email protected]. Missing December 31 costs you the whole year, because the City doesn't backdate.
Take your annual charge, halve it, and compare that against the cost of a P.Eng report. On a large site paying several thousand a year, 50% for five years usually clears the engineering cost in the first year.
A big detached house carries $219.13 a year in stormwater before you've turned a tap on. Put it in the column next to property tax and utilities — our Property Tax Estimator handles the larger half of that math.
The tier is the only lever a homeowner has. You can't opt out, you can't earn a residential credit, and conservation on your own property won't move the number. Either the City measured your roof right or it didn't — and checking takes about two minutes on the estimator.
Useful links — directly from the source
Every figure in this article comes from the City of Mississauga and the Region of Peel. Use the links below to check your own property and start any application.