How to Draft a Legally Compliant Lease or Addendum

Why the Ontario Standard Lease form matters

For most residential tenancies in Ontario, landlords are generally required to use the government's Ontario Standard Lease form as the base document, rather than a lease drafted entirely from scratch. This requirement generally applies to most private residential tenancies, with some exceptions such as care homes, mobile home parks, and certain non-profit or co-operative housing. Using the correct base form is generally the starting point for a compliant lease, and it is worth confirming whether your tenancy falls within scope before drafting anything.

Our guide on whether landlords should use the standard lease form or something else goes further into this question, including what happens if a landlord fails to use the required form when they should have. In general, a failure to use the required standard lease when it applies doesn't void the tenancy itself, but it can affect a landlord's ability to enforce certain lease terms and may give the tenant the right to ask for the form to be provided and to withhold some obligations until it is.

Step 1: Choose and confirm your base document

Before adding any custom terms, make sure the foundation itself is right.

1. Confirm whether your tenancy type requires the Ontario Standard Lease form, since most private rentals of a room, apartment, or house generally do.
2. Download the current version of the form from a reliable government source, rather than reusing an old template that may be outdated.
3. Fill in the basic tenancy details accurately — the parties, the address, the rent amount, the term, and the services included — since errors here can create confusion or disputes later.
4. If your tenancy is genuinely exempt from the standard lease requirement, confirm this carefully before drafting a custom lease instead, since getting this wrong can expose you to later disputes about which terms actually apply.

Step 2: Include the terms the RTA requires

A compliant lease generally needs to reflect certain baseline terms the RTA requires or implies, regardless of what the parties might prefer to agree to instead.

1. State the rent amount, due date, and accepted payment methods clearly.
2. Record any deposits collected, such as a last month's rent deposit, and confirm the amount matches what is actually permitted (generally no more than one month's rent, or one week's rent for a weekly tenancy).
3. Set out what services and utilities are included in the rent, and which are the tenant's own responsibility.
4. Avoid including any clause that purports to waive the tenant's rights under the RTA, such as a clause claiming the landlord can enter the unit without notice, since this generally has no legal effect even if included.

Our RTA vs. your lease guide explains in more detail why terms that conflict with the RTA are generally unenforceable regardless of what the lease document says.

Step 3: Draft a compliant addendum for extra terms

Landlords often want to add terms beyond what the standard lease form itself covers — house rules, parking arrangements, pet-related provisions, or other building-specific matters. These generally need to go into a separate addendum attached to the standard lease, rather than altering the standard form itself.

1. Draft the addendum as a clearly labelled, separate document, referencing the main lease and the unit address.
2. Keep additional terms specific and reasonable — for example, rules about noise, parking spot assignments, or storage locker use — rather than vague or overly broad restrictions.
3. Avoid including anything in the addendum that would conflict with RTA protections, since an addendum term is just as vulnerable to being found void as a term in the main lease itself.
4. Have both the landlord and tenant sign and date the addendum, and keep a copy attached to the signed lease on file.

Step 4: Check for clauses that won't hold up

Certain categories of clauses come up repeatedly in leases and generally do not hold up if challenged, regardless of how they're worded.

1. Blanket "no pets" clauses, which are generally unenforceable for most residential tenancies under the RTA, even though a landlord may still be able to address specific pet-related problems separately.
2. Clauses purporting to let the landlord enter the unit at will or without proper notice, which conflict with the entry and privacy protections discussed in our landlord entry and tenant privacy guide.
3. Automatic rent increase clauses that bypass the RTA's notice and timing requirements.
4. Clauses attempting to waive a tenant's right to apply to the LTB, or to require disputes to go through a different process entirely.
5. Excessive fees for things like late rent payments or bounced cheques that exceed what is generally permitted.

Step 5: Review and sign properly with the tenant

Once the lease and any addendum are drafted, how the signing itself happens generally matters for enforceability and for avoiding later disputes. A lease signed under pressure, without a real chance to read it, can later become a point of contention even if its substance is otherwise sound, so treating this step as more than a formality tends to serve both sides well.

1. Give the tenant a reasonable opportunity to read the full lease and addendum before signing, rather than presenting it as a rushed, final step at move-in.
2. Answer any questions the tenant raises about specific terms honestly and clearly.
3. Have both parties sign and date every page that requires a signature, and provide the tenant with a complete, signed copy for their own records, which is generally a legal requirement.
4. Keep your own signed copy, along with any addendum, safely on file for the duration of the tenancy and afterward.

What happens after the lease is signed

Once signed, the lease and any properly attached addendum generally govern the tenancy going forward, alongside the RTA's own baseline protections, which always apply regardless of what the lease says. If a dispute arises later about a specific clause, the LTB will generally interpret the lease in light of the RTA, and any term found to conflict with the Act will generally be treated as if it were never part of the agreement, even though the rest of the lease generally remains valid.

It's worth revisiting your lease and addendum templates periodically, since the RTA, its regulations, and the standard lease form itself are occasionally updated, and a template that was compliant when first drafted may need adjustments later.

Common mistakes that make a lease unenforceable

A number of recurring drafting mistakes tend to undermine leases that otherwise look professional and thorough.

1. Using an outdated version of the standard lease form instead of the current one.
2. Including blanket restrictions, such as a no-pets clause, that are generally unenforceable regardless of how firmly they're worded.
3. Trying to use an addendum to smuggle in terms that would be void if placed directly in the lease.
4. Failing to provide the tenant with a signed copy of the lease, which is generally a requirement in its own right.
5. Collecting a deposit amount that exceeds what is generally permitted, or failing to document it properly within the lease.

Frequently Asked Questions

Related reading

Reviewed by Ryan J. Manilla, BA, JD

Legal Reviewer · Landlord Tenant Ontario