The owner answers to the City for backflow testing, but the lease or condo declaration decides who pays. Here is who usually covers the cost in each situation and how to write it down.
The annual backflow test invoice has landed and three people are now pointing at each other: the landlord, the tenant running the restaurant on the ground floor, and the condo board that owns the mechanical room. Someone has to pay. The City, for its part, does not care who — it only cares that a passing report is filed on time.
Quick answer
- The property owner is legally responsible to the municipality for backflow testing and filing, no matter who pays the invoice.
- A lease or condo declaration can shift the cost to a tenant or the condo corporation, but it cannot shift the legal responsibility.
- Under a net lease the tenant usually pays; under a gross lease the landlord usually pays.
- In a condo, a device on a common element is a corporation expense; a device inside a unit serving only that unit is usually the unit owner’s.
- Whoever pays, the owner should receive a copy of the filed report.
Who is legally responsible for backflow testing?
The property owner. In Toronto, the Water Supply By-law (Chapter 851) places the duty to test every device once every 12 months and to file the report with Toronto Water on the owner, and the other GTA municipalities take the same approach.
That duty covers industrial, commercial and institutional properties, Part 3 residential buildings under the Ontario Building Code, construction sites and any property identified through a cross-connection control survey.
A contractor, tenant or property manager can do the booking and the paying. If the report is never filed, though, the compliance notice is addressed to the owner.
Who usually pays in each situation?
It depends on what the lease or condo documents say, but there are common patterns. The table shows who normally carries the cost and who the City holds responsible, which is always the owner.
| Situation | Who usually pays | Who the City holds responsible |
|---|---|---|
| Owner-occupied building | The owner | The owner |
| Net lease (tenant pays operating costs) | The tenant, directly or through operating-cost recoveries | The owner |
| Gross lease (rent includes operating costs) | The landlord | The owner |
| Condo common-element device | The condo corporation, from the operating budget | The corporation, as owner of the common elements |
| Device inside a unit, serving only that unit | Usually the unit owner, subject to the declaration | The registered owner |
| Tenant-installed device (restaurant, clinic, car wash) | The tenant, if the lease says so | The owner |
Tenant-installed devices: a restaurant that adds a carbonator or a clinic that installs sterilization equipment often installs its own backflow preventer. The tenant may own the valve, but it sits on the building’s water service, so the property owner still answers for its annual test.
What should the lease say about backflow testing?
The lease should name each device, say who books and pays for the annual test, and require that a copy of the filed report goes to the landlord. Vague phrases such as “tenant maintains plumbing” cause most of the disputes we hear about.
Four clauses do most of the work:
- Identify each backflow preventer by location and serial number in a schedule to the lease.
- State who arranges and pays for the annual test and any repair, including the Toronto rule that a repaired device is retested within 72 hours.
- Require the tester to be a certified Cross Connection Control Specialist who files the report with the municipality.
- Require a copy of every report, pass or fail, to reach the landlord within a set number of days.
Prefer not to referee this every year? We test, tag, file and send the report to both parties — $350 for a single device, less per device for multi-device sites. Get a fixed quote or call (647) 578-9903.
How do condo corporations handle backflow testing costs?
Most condo corporations treat backflow testing as a recurring operating expense, because the main device sits on a common element and protects the whole building. A Part 3 residential condo in Toronto falls squarely inside the by-law.
Budget for it the way you budget for fire alarm or elevator inspections: a fixed line item, one vendor, one visit for every device on the property.
Devices inside commercial units at the base of a tower are the grey area. Check the declaration; if it is silent, the corporation should still make sure the test happens and recover the cost afterwards rather than let a unit fall behind.
Who should receive the test report copy?
The municipality receives the filed report, and the owner should always receive a copy, because the owner is the party the City will contact. In Toronto the tester submits through the City’s online Backflow Prevention Device Test Report form.
Beyond that, send copies to whoever pays and whoever manages the building. A property manager who holds every report in one folder closes a City notice in minutes instead of weeks.
Backflow Inspector, a service of MT Drains & Plumbing, issues a digital report for every test and will copy it to the owner, the tenant and the manager on request. Not sure whether your property is covered at all? Use the 30-second eligibility check.
Quick answers
Stop the back-and-forth over who books the test
We test every device, file the report and send a copy to the owner, tenant and manager — $350 for a single device, with a fixed quote before you book.