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Plumbing Permits in Ontario (2026): What Needs One and What Does Not, Who Applies, the Inspection Stages, Toronto Fees, Water Heaters and Work That Was Never Permitted
Plumbing & Water
The Plumbing Permit: Cheap to Get, Expensive to Skip
A basic plumbing permit in Toronto is about $205. Skipping one can cost you a ceiling, a sale or an awkward talk with your insurer, which is a poor trade for two hundred dollars. This page covers what needs a permit, who applies, the inspections, Toronto’s fees as an example, water heaters and backwater valves, and plumbing somebody did without one.
What Needs a Permit, and What Does Not
Ontario builds to the Building Code, O. Reg. 163/24, the 2024 Code. It came into force January 1, 2025 and has been mandatory for every new permit application since April 1, 2025. Plumbing is Division B, Part 7, adopted from the 2020 National Plumbing Code with Ontario changes; its numbering now follows the national code more closely, so article numbers in older guides may have moved. The permit comes from your municipal building department.
The municipal rule is short: you need a permit to install, extend, alter, renew or repair plumbing. Then the guidance carves out the small stuff.
| Job | Permit? | Why |
|---|---|---|
| Replace a toilet, sink or faucet in the same spot | Usually no | Same location, same drain |
| Fix a leak, replace a trap, clear a blocked drain | Usually no | Minor repair |
| Add a bathroom, or move a toilet, sink or shower | Yes | Adding or moving fixtures |
| New drain, new stack, new floor drain | Yes | New drainage piping |
| New or replaced water service | Yes | New water service |
| Backwater valve, or a sump with a pump | Yes | Toronto lists both in its fee table |
| Plumbing a new house or an addition | Yes | Every fixture is new |
| Replace a water heater | Check locally | Some municipalities want one, especially for gas or a change of type |
Rules vary a little from one municipality to the next; the building department’s website or a phone call settles it. The wider question of decks, basements and additions is on the do I need a building permit page.
Who Applies, and Who Does the Work
On most jobs either you apply as the owner or the plumber applies for you; the application form says who may sign. Either way the permit is tied to your address, and so is the trouble if it never gets closed.
Plumber is a compulsory trade in Ontario. Anyone you hire to do plumbing must hold a Certificate of Qualification, a provisional certificate, or be a registered apprentice working under a certified plumber. Check them on the Skilled Trades Ontario public register, by name or ID number. The hiring page goes through the rest of the paper.
In most Ontario municipalities you can do the plumbing in a house you own and live in, but you still need the permit and the inspections, and you cannot hire an unlicensed person to do it for you. Check with your building department first.
Gas piping and gas water heaters are a different licence entirely. That work is regulated by TSSA and done by a registered gas contractor with a certified gas technician. It is never a homeowner job. On our own builds and renovations in Simcoe, Muskoka and Georgian Bay, the plumbing is done by licensed plumbers we hire; I am the builder, not the plumber.
The Inspections That Come With It
A permit is really a booking for inspections. Municipal guidance sets out four stops, and the rule at every one of them is the same: nothing gets covered before it is inspected.
| Stage | Inspected before |
|---|---|
| Building sewer, storm sewer and water service | Backfill |
| Groundwork: the under-slab plumbing | Backfill and the concrete floor pour |
| Rough-in drain, waste and vent piping, water-tested to the roof line | Walls and ceilings are covered |
| Fixtures | Use and occupancy |
Book each inspection about 2 business days ahead. What the inspector actually looks at is on the plumbing basics page; the homeowner’s own list for each stop is the plumbing inspection checklist.
The groundwork stop is the one that matters most in our houses. We build ICF houses with hydronic radiant floors, and the radiant tubing is tied down in the basement before the slab is poured, so the drains, the sump pit and any future bathroom rough-in have to be placed, inspected and protected before the pour too. After the pour, a forgotten drain is a jackhammer.
What Toronto Charges, as an Example
| Toronto standalone plumbing permit | Fee | Source |
|---|---|---|
| Basic plumbing permit, up to 5 fixtures | $205 | a Toronto plumber’s summary |
| Each fixture beyond 5 | $16 | same summary |
| Water service replacement permit | about $245 | same summary |
| Backwater valve, or sump with a pump, each | $38.67 | the City’s fee table |
| Buried water service, sanitary and storm piping, single-family house | $214.79 flat | the City’s fee table |
| Permits and inspections for a basement bathroom, all in | $300 to $800 | a Canadian renovation cost guide |
| Backwater valve permit, Ontario range | $100 to $300 | published Ontario ranges |
October 2026 prices. Other municipalities charge differently; some by fixture, some by the value of the work. Check yours before you budget.
Why Ontario prices are all over the map: the permit is the cheap line. The work it covers is not, and the contractors and price guides we checked could not agree on that either. For a backwater valve, a national renovation marketplace said $2,000 to $4,500 in the GTA, typically $2,800, and $1,800 to $3,800 in Ottawa. A Canadian building guide said $1,500 to $5,000 in Toronto. A national marketplace average was about $6,000 in Toronto, likely with more scope in it. Inside or outside, how much floor comes up, the assessment and the city make the gap. Budget $2,800, and get two or three quotes on the same written scope.
A worked case: two bathrooms redone with three fixtures each, plus the kitchen sink and a laundry tub moved, is 8 fixtures. At the summary’s rate that is $205 + 3 x $16 = $253. Add a backwater valve from the City’s own table and it is $253 + $38.67 = $291.67.
Backwater Valves and the Subsidy Permit
A backwater valve is a one-way door for your sewer. Under Article 7.4.6.4, one is required on a fixture drain where the fixture is below the level of the adjoining street, and where a house is on a public sewer, fixtures below the upstream sanitary manhole cover must be protected. A valve in the building drain must be a “normally open” type and serve no more than one dwelling unit.
The subsidy programs care about the permit more than anyone. Toronto’s Basement Flooding Protection Subsidy pays 80 percent of the invoice, up to $1,600 for each backwater valve with an alarm, but it wants a building permit for the valve, a contractor with a City of Toronto business licence, disconnected downspouts, and a valve that was not covered before inspection. If you qualify, on a $2,800 valve: 80 percent is $2,240, the cap is $1,600, so the subsidy is $1,600 and you pay $1,200. Apply within 2 years; it is first come, first served.
Ottawa’s Residential Protective Plumbing Program wants the permit first, then pays 100 percent of the permit fee plus the lesser of the cost or $1,000 for an indoor sanitary backwater valve, for houses built before January 1, 2012. If you qualify, a $2,400 valve gets $1,000 back and you pay $1,400, with the permit fee covered. Check before you book; the details are on the sump pump and backwater valve page.
Plumbing That Was Never Permitted
It is common, especially in basements finished on a long weekend. It bites at two moments: when you sell and a buyer’s lawyer or home inspector starts asking, and when water comes through a ceiling and the insurer starts asking. Ask your broker in writing what they need, before there is a claim.
Many building departments can tell you what permits were issued for your address. If the bathroom was never permitted, the usual fix is to apply now and let the inspector see the work, which can mean opening a wall or ceiling. Budget drywall access and repair at $500 to $2,000 in finished areas, often more for plaster.
Water heaters sit in a grey zone. Some municipalities want a permit for a replacement, especially for gas or a change of type; check locally. A gas heater is TSSA work by a registered gas contractor whatever the building department says. If you rent your tank, the rent or buy page covers getting out of it.
Questions people ask
Do I need a permit to replace a toilet in Ontario?
Usually not, if it goes back in the same spot on the same drain. Moving it, or adding one, needs a permit. A call to the building department settles it.
Can a homeowner get a plumbing permit in Ontario?
In most Ontario municipalities you can do the plumbing in a house you own and live in, but you still need the permit and the inspections, and you cannot hire an unlicensed person to do it for you. Check with your building department first.
How much is a plumbing permit in Toronto?
A Toronto plumber’s summary puts the basic permit at $205 for up to 5 fixtures plus $16 for each one beyond 5. The City’s own table lists a backwater valve or a sump with a pump at $38.67 each. Other municipalities charge differently.
When does the plumbing inspector come?
Before the sewer and water service are backfilled, before the under-slab plumbing is buried and the floor poured, at rough-in before the walls are covered, and at the fixtures before you move in.
Do I need a permit for a backwater valve?
Yes. And if you want a subsidy, Toronto and Ottawa both want the permit, and Toronto wants the valve left uncovered until it is inspected.
Price the plumbing before you price the permit
The plumbing cost estimator gives you the number for the work itself, by fixture, with municipal or well and septic, basement or slab. If you already have quotes, the $99 review reads up to three of them and tells you whether the permit, the inspections and the patching are actually in them.
Sources and further reading
- The 2024 Ontario Building Code: Ontario on the 2024 Code: in force January 1, 2025, the grace period to March 31, 2025, and the harmonization with the national codes.
- A municipal guide to plumbing permits (Thunder Bay): what needs a plumbing permit and the inspection stages, from underground to final.
- Toronto standalone plumbing and drain permits: what a plumbing permit covers in Toronto and the published fees.
