Co-Signers and Guarantors on an Ontario Lease

A guarantor — sometimes called a co-signer, though the two terms are generally used interchangeably — is someone who agrees to stand behind a tenant’s financial obligations under a lease. In plain terms, if the named tenant doesn’t pay rent, the guarantor has generally agreed that the landlord can look to them for payment instead, or in addition.

This is a distinct role from being a tenant. A guarantor generally doesn’t sign the lease as an occupant, doesn’t gain the right to move into the unit, and doesn’t take on the day-to-day responsibilities a tenant has, such as keeping the unit reasonably clean. What they take on instead is financial exposure: a promise, usually set out in a separate guarantee agreement or a specific clause added to the lease, that they’ll cover certain amounts if the tenant doesn’t.

Because a guarantor’s obligations come entirely from the wording of whatever they sign, there’s no single standard version of what a guarantee covers across every Ontario tenancy. Some guarantees are narrowly limited to unpaid rent for a specific period; others are written broadly enough to capture damage costs, legal costs, or other amounts owed under the tenancy. Reading the actual document, rather than assuming it works a certain way, matters a great deal here.

It’s also worth noting that a guarantee is usually a contract in its own right, separate from the lease itself, even though it’s often presented alongside it as part of the same signing package. That separation matters because it means the guarantor’s obligations are governed primarily by the wording of the guarantee document, rather than automatically mirroring every term of the lease the tenant signed.

It’s easy to conflate a guarantor with a co-tenant, but the two roles work quite differently. A co-tenant is named directly on the lease alongside any other tenants, has the right to live in the unit, and is generally jointly and severally liable for the full rent — meaning the landlord can pursue any one co-tenant for the whole amount owed, not just their “share.”

A guarantor, by contrast, typically isn’t named as a tenant and generally has no right to occupy the unit at all. Their involvement is purely about backing someone else’s obligations, usually because the landlord wants additional financial assurance beyond what the named tenant can offer on their own. This distinction matters for a simple reason: the rights and protections that come with being a tenant under the Residential Tenancies Act generally attach to tenants, not to guarantors.

Landlords commonly ask for a guarantor when a prospective tenant’s income, credit history, or rental history doesn’t, on its own, give the landlord enough comfort that rent will be paid reliably. This comes up often with students, newcomers to Canada who haven’t yet built local credit history, or tenants whose income is variable or difficult to verify through conventional means like pay stubs.

Asking for a guarantor is generally a business decision on the landlord’s part, made during the screening process before a tenancy begins, rather than something imposed partway through an existing tenancy. A tenant isn’t generally required by law to provide one, but refusing may affect whether a particular landlord is willing to proceed with that specific applicant.

It’s worth noting that asking every applicant for a guarantor as a blanket, inflexible policy is different from assessing each application individually. Screening criteria generally need to be applied consistently and can’t be used as a pretext for treating applicants differently based on a protected ground under Ontario’s human rights legislation, even though the general practice of requesting a guarantor in appropriate circumstances is a legitimate screening tool.

One of the most important — and most overlooked — questions is how long a guarantee actually continues. Many guarantee documents are drafted to remain in effect for as long as the underlying tenancy continues, which can mean the guarantee stays alive well past the end of an initial fixed term if the tenancy simply rolls into a month-to-month arrangement afterward.

This can catch guarantors off guard. Someone who agreed to guarantee a one-year lease might reasonably assume their obligation ends when that year is up, but if the guarantee document doesn’t clearly say so, and the tenancy continues on a month-to-month basis, the guarantee may well continue right along with it. Our article on ending a lease agreement in Ontario explains how fixed terms transition into ongoing tenancies, which is directly relevant to understanding when a guarantee tied to “the tenancy” might actually end.

Some guarantee documents are drafted more narrowly, limiting the guarantor’s exposure to a specific fixed term or a specific dollar amount. Where that kind of limiting language exists, it generally needs to be clear and explicit — a vague or ambiguous reference to “the lease” is often interpreted, in practice, as covering the tenancy for as long as it continues, including any renewal or month-to-month period that follows.

The core risk for a guarantor is straightforward: if the tenant stops paying rent, the landlord can generally pursue the guarantor for the amounts owed under the terms of the guarantee, regardless of whether the guarantor ever lived in the unit, met the landlord, or was involved in the day-to-day tenancy at all. This exposure exists independently of the tenant’s own circumstances — a guarantor generally can’t avoid liability simply because the tenant has since become unreachable or unable to pay.

Guarantors should also be aware that the process for pursuing a claim against them isn’t always identical to the process used against the tenant directly, since a guarantor generally isn’t a tenant for purposes of the Residential Tenancies Act. Depending on how the claim is framed, a landlord may need to pursue a guarantor through a different process than the one used for a standard Landlord and Tenant Board application against a tenant.

There’s also a practical, relational risk worth naming directly: acting as a guarantor for a friend or family member means taking on financial exposure tied to someone else’s behaviour, often over a period of a year or more. Even where the tenant has every intention of paying on time, job loss, illness, or a falling-out between roommates can all affect whether rent actually gets paid — risks the guarantor has little direct control over once they’ve signed.

Anyone asked to act as a guarantor should read the actual guarantee document closely rather than relying on a general understanding of what the role involves. Key questions include exactly what debts are covered, whether the guarantee is capped at a specific amount or time period, whether it continues automatically if the tenancy is renewed or becomes month-to-month, and what steps the landlord would need to take before seeking payment from the guarantor directly.

It’s also worth having a candid conversation with the tenant being guaranteed, since the guarantor’s financial exposure is directly tied to that person’s ability and willingness to pay rent on time. For a broader look at how Ontario residential leases are generally structured, see our guide to lease agreements in Ontario, and visit the Leases hub for related topics.