What this calculator answers
A renewal letter often arrives with one rate and a signature line. Signing it is easy, but the rate is not always the best your lender or another lender would give you. This calculator puts your renewal offer next to up to two offers from other lenders and measures every one over the same number of months.
It counts what you actually pay: the monthly payments, any switching costs you cover yourself, any cashback, and the balance you still owe at the end. That last part matters: an offer with a longer amortization has a lower payment but leaves you owing more.
How the calculation works
- Each offer is run month by month from the same starting balance. Fixed rates use semi-annual compounding, as Canadian fixed mortgages do. Variable rates use the compounding you choose under More options (monthly by default) and are held steady.
- Total cost = cash costs minus cashback, plus all payments, plus the balance left at the end of the comparison period.
- By default the period is the shortest term among the offers, so every offer is compared while its rate is locked in.
- The difference column shows how much more each offer costs than the cheapest one over that period.
Assumptions and limits
- Rates shown as defaults are examples only, not rate quotes. Enter the offers you actually have.
- Switch costs vary. Many lenders cover legal and appraisal costs for a switch, and some do not. Your current lender may charge a discharge fee set in your contract. This is lender policy, not regulation.
- Prepayment privileges, penalty calculation methods, portability and charge type are not modelled, but they can matter more than a small rate difference.
- Stress test (regulation): Qualify at the greater of 5.25% or your contract rate plus 2%. Applies to uninsured mortgages at federally regulated lenders (OSFI Guideline B-20) and to insured mortgages (federal insured-mortgage rules). Since November 2024 an uninsured straight switch at renewal is exempt. A straight switch generally means the same balance and the same remaining amortization. Borrowing more or extending the amortization is treated as new lending. Provincially regulated lenders such as credit unions set their own rules.
- Being offered a rate is not an approval. A new lender still reviews your application, property and credit.
Common questions
Can I negotiate my renewal rate?
Often, yes. The first rate in a renewal letter is not always the lowest your lender will offer. Having a written offer from another lender gives you something concrete to ask them to match.
Do I need to pass the stress test to switch lenders at renewal?
For an uninsured mortgage moving to a federally regulated lender as a straight switch (same balance, same amortization), OSFI removed the stress test requirement in November 2024. If you add money or extend the amortization, expect to be qualified as a new mortgage. If your mortgage is insured or you are moving to a credit union, ask how they treat a switch.
When should I start comparing?
Many lenders let you renew or arrange a switch a few months before your maturity date, often up to about 120 days. The window is set by each lender, so check your renewal letter and ask the new lender how long they hold a rate.
Is a cashback offer worth it?
It can be, if the rate is otherwise competitive and you keep the mortgage for the full term. Cashback usually has to be repaid if you break early, and cashback mortgages sometimes carry a higher rate. The calculator counts cashback against cost so you can see the net effect.
Why does a lower rate sometimes lose?
Costs you pay to switch, a longer amortization that leaves more owing, or a shorter comparison period can all close the gap. Small rate differences on smaller balances can also be outweighed by a few hundred dollars of costs.
Sources
- OSFI: minimum qualifying rate (rules checked 2026-10-31)
- Interest Act, section 6 (rules checked 2026-10-31)
- FCAC: prepayment penalties (rules checked 2026-10-31)