Last updated: September 2026
A cosigner for a house loan is someone who signs the mortgage with you and agrees to repay it if you can’t. For Canadians with a thin credit file or hard-to-document income, a cosigner is often the difference between an approval and a polite “no”, but it is a serious favour to ask, because the cosigner is on the hook for the full balance.
Canadian Debt Relief is an independent Canadian guide to debt relief options — consumer proposals, debt management plans, debt consolidation and bankruptcy — for people who want to understand their choices before they talk to anyone.
What is a cosigner for a house loan in Canada?
A cosigner is a second borrower who signs the mortgage contract and, in most cases, goes on the property title, making them fully responsible for the entire loan.
The Financial Consumer Agency of Canada (FCAC) says in its 2026 guide on preparing to get a mortgage that a lender may require someone to cosign if your credit score isn’t good enough. The same FCAC page sets the two ratios lenders use: housing costs should stay under 39% of gross household income (the GDS ratio) and total debt payments under 44% (the TDS ratio).
A cosigner is not a guarantor: as Ratellow’s 2026 guide on co-signers versus guarantors explains, a guarantor pays only if you default and stays off title, while a cosigner is a co-borrower from day one. Your credit score range usually decides whether the lender asks for one.
What are the pros and cons of using a cosigner?
The main advantage is approval: a cosigner can move you from declined to approved, and often from an alternative lender to a prime rate, which on a $500,000 mortgage is worth roughly $280 to $900 a month. The main disadvantage is that the cosigner carries full liability and the mortgage sits on their credit report.
Who should consider a cosigner, and who shouldn’t?
A cosigner makes sense when the only thing between you and approval is a short credit history or hard-to-document income, and you can afford the payment alone. It doesn’t make sense when the payment itself is the problem, because a cosigner doesn’t lower your monthly cost.
- Have a credit score below about 680 because your file is new, not because of missed payments.
- Are self-employed or on probation at a new job and can’t yet show two years of income.
- Can carry the mortgage, property taxes and heating on your own income at 39% GDS or less.
- Carry $20,000 or more in credit card or other unsecured debt that already squeezes your budget.
- Would still be above 44% TDS even with the cosigner’s income added.
- Are asking someone near retirement, or who plans to borrow for their own needs soon.
If unsecured debt is pushing your ratios over the line, dealing with it first usually beats leaning on a cosigner; a consumer proposal example shows how. Our guide to bad credit home loans in Canada covers the alternative-lender route if no cosigner is available.
How much difference does a cosigner make?
On a $450,000 purchase with 10% down, a borrower earning $70,000 with a $450 car payment and $12,000 in credit card debt fails the 44% TDS limit alone at 68%, but adding a cosigner earning $65,000 with no debt brings the household TDS to 35% and the application through. The figures use a 4.5% fixed rate, stress-tested at 6.5% under the federal rule of your contract rate plus two percentage points (or 5.25%, whichever is higher).
Notice what didn’t change: the real payment on $405,000 at 4.5% over 25 years is $2,242 a month with or without the cosigner, and the primary borrower still has to make it. A cosigner solves an income problem, not a debt problem. Run your own numbers with CMHC’s mortgage payment calculator.
How do you add a cosigner to a mortgage?
Adding a cosigner takes about as long as a normal application, usually two to four weeks from pre-approval to funding, and the cosigner goes through the same income and credit checks you do.
- Get pre-approved on your own first. Ask a broker or lender how far short you fall and why.
- Choose the right cosigner. Look for a credit score of 680 or higher, stable income, and a TDS ratio under about 30% before your mortgage is added. See our guide to improving your chances of loan approval.
- Agree the terms in writing. Who pays what, what happens after a missed payment, and when you plan to remove the cosigner.
- Submit the joint application. The cosigner provides pay stubs, a notice of assessment, ID and consent to a credit check.
- Get the cosigner independent legal advice. As Insight Law Firm notes in its 2026 guide to co-signing a real estate loan, a cosigner on title is personally and fully liable, so most lenders require their own lawyer’s sign-off.
- Set a date to requalify alone. Most lenders will consider removing a cosigner after 12 to 24 months of clean payments if you can then qualify on your own.
How do you remove a cosigner from a mortgage?
You remove a cosigner by requalifying for the mortgage alone, either at renewal or through a refinance, which typically costs $1,000 to $3,000 in legal and appraisal fees plus a prepayment penalty if done mid-term. You must prove you now meet the GDS, TDS and stress-test limits by yourself.
The practical timeline is two to five years. If the cosigner is on title, removing them also means a title transfer, which can trigger land transfer tax in some provinces. Our guide to mortgages and debt management plans explains how renewals work if you’re on a repayment program.
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Frequently asked questions
Who can be a cosigner for a house loan in Canada?
Any adult Canadian resident with a credit score of about 680 or higher, verifiable income and room in their own debt ratios can cosign a mortgage in Canada. Lenders prefer close family, most often parents. The cosigner doesn’t have to live in the home but is usually placed on title.
Does cosigning a mortgage affect the cosigner’s credit score?
Yes. Cosigning a mortgage puts the full mortgage on the cosigner’s credit report, and the entire monthly payment counts against their debt ratios when they apply for their own credit. A missed payment lowers the cosigner’s score just as much as yours and stays on their file for six years.
Can a cosigner be removed from a mortgage in Canada?
Yes, but only by the primary borrower requalifying alone through a refinance or at renewal, which typically takes two to five years of clean payments and costs $1,000 to $3,000 in legal and appraisal fees.
What happens to the cosigner if the borrower stops paying?
If the borrower stops paying, the lender can demand the missed amount from the cosigner immediately, report the arrears on their credit file, and pursue them for the entire balance. On a $405,000 mortgage, the cosigner is responsible for the whole $405,000 plus arrears and costs, not a portion of it.
Can I get a mortgage with a cosigner if I have a consumer proposal?
Usually not while the proposal is active. Most A-lenders want a consumer proposal paid off and about two years of rebuilt credit before approving a mortgage, even with a strong cosigner. Only a Licensed Insolvency Trustee can file a consumer proposal, and paying one off early is one of the fastest ways back to a prime mortgage.
After 20 years of structuring multi-million dollar corporate debt facilities and corporate turnarounds in investment banking, Marcus now leads Canadian Debt Relief to apply those exact same balance-sheet optimization frameworks to Canadian household debt.
