What Happens If a Landlord Increases Rent Without Proper Notice?

What "proper notice" actually requires

Under the Residential Tenancies Act, 2006 (RTA), a landlord generally cannot increase rent simply by mentioning it, sending a casual email, or posting a notice in a common area. The Act generally requires a specific form of written notice, given at least 90 days before the increase is meant to take effect, that clearly states the new rent amount and the date the increase begins. This notice generally has to use the form the province has designated for this purpose. The point of these requirements is to give tenants a defined, predictable amount of advance warning and a document they can actually check against the rules — not simply a landlord's informal say-so about a new amount owing.

Common ways a rent increase notice falls short

Several recurring problems come up when a rent increase notice doesn't hold up. Sometimes the notice period is too short — the landlord gives 60 days instead of the required 90. Sometimes the increase comes too soon after the tenancy began or after the last increase, violating the 12-month spacing rule regardless of how much notice was given. Sometimes the notice simply isn't in writing at all, and the landlord has instead raised the issue verbally or through an informal text message that doesn't meet the legal form requirements. And sometimes the percentage itself is the problem — the increase exceeds that year's guideline without the landlord having obtained the LTB's approval for an above-guideline increase.

Occasionally the issue is more subtle, such as a notice that gives the correct amount of time but miscalculates the actual effective date, or one that fails to clearly state the new rent amount in a way the tenant can verify against the current rent. Even a notice that looks mostly correct at a glance can have one of these smaller defects buried in it, which is why it's generally worth checking every element rather than just skimming for the headline percentage.

What an improperly noticed increase means legally

When a rent increase doesn't meet the RTA's notice and timing requirements, it is generally not legally enforceable as given. In practical terms, this generally means the tenant's lawful rent remains the previous amount until a compliant notice is served and the required notice period has actually elapsed. The increase doesn't automatically become valid just because time has passed since it was announced, and it doesn't become valid simply because the tenant didn't immediately object — though a tenant who starts paying the higher amount can create its own complications, discussed below.

If a tenant has already been paying the higher amount

It's fairly common for a tenant to simply start paying an increased amount, either because they didn't realize the notice was defective or because they didn't want to create friction with the landlord. If it later turns out the increase wasn't properly noticed, a tenant generally has options to recover the difference — for example, by applying to the LTB for a rent abatement or order requiring the landlord to credit or repay the amount collected above the lawful rent. The fact that a tenant paid the higher amount for a period of time generally does not, on its own, turn an improperly noticed increase into a valid one; it generally just means there may be money to sort out once the defect is identified.

This can matter well after the fact, too — a tenant who only realizes months or years later that an old increase was never properly noticed may still be able to raise the issue, since the underlying defect doesn't generally heal itself just because nobody flagged it at the time. That said, timelines for bringing a claim can matter, which is one more reason it's worth addressing a questionable notice sooner rather than later.

Verbal or informal "increases" with no notice at all

Some disputes arise not from a defective written notice but from no written notice at all — a landlord mentions during a conversation, or in a casual email, that rent "will be going up" starting a certain date, without ever serving the legally required form. In that situation, there generally is no valid increase in place, regardless of what was discussed informally, because the RTA's notice requirement generally isn't satisfied by conversation alone. A tenant who receives this kind of informal heads-up is generally not obligated to start paying a higher amount until a proper written notice has actually been served and the notice period has run.

How a landlord generally fixes a defective notice

When a landlord realizes a notice was defective — too short a notice period, the wrong form, or an improperly calculated percentage — the general remedy is to serve a new, compliant notice and restart the required notice period from that new date. There is generally no shortcut that lets a landlord simply "fix" the original defective notice retroactively or treat the original date as still valid once the problem is corrected. This can mean a meaningful delay before a corrected increase actually takes effect, which is part of why getting the notice right the first time tends to matter, especially for a landlord managing several units where the same template notice is reused across multiple tenancies.

Steps a tenant can take in response

A tenant who receives a rent increase notice that looks off has a few practical options. The first is simply to check the notice against the requirements — is it on the right form, does it give at least 90 days, does it fall at least 12 months after the tenancy began or the last increase, and does the percentage match or fall below that year's guideline (unless an AGI was actually approved). If something doesn't line up, the tenant can generally continue paying the previous lawful rent and raise the issue directly with the landlord, in writing, explaining the specific defect. If that doesn't resolve things, the tenant can generally bring the matter to the LTB.

When it's worth getting outside help

Most individual notice defects are fairly easy to spot once a tenant knows what to check for. Where things tend to get more complicated is when there's a dispute about facts — for example, disagreement about exactly when notice was given, or about whether a tenancy has had intervening changes that affect the 12-month calculation. A long tenancy with several past increases, an assignment, or a period where rent was reduced for some reason can all make it harder to simply look at the current notice and know for certain whether the timing lines up.

In those situations, reviewing the LTB's own published guidance, or speaking with a paralegal or community legal clinic, can generally help a tenant or landlord understand where they actually stand before a hearing becomes necessary. Keeping a simple written timeline — when the tenancy started, every notice received, and every increase that actually took effect — tends to make this kind of review much faster, whether it's a tenant checking their own history or someone helping them sort through it.

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Reviewed by Ryan J. Manilla, BA, JD

Legal Reviewer · Landlord Tenant Ontario