Rates aren't the only cost
Rates aren't the only cost: mortgage strategy in Ontario
Written by Stonefield Mortgage · Reviewed by David Steinfeld, principal broker · Stonefield Mortgage, FSRA mortgage brokerage licence #13722 · [review pending — before this page is indexed]
Published · Updated
In Ontario, the rate is one line of a mortgage plan, and for many borrowers it isn't the line that decides the cost. What the property is for, how long you'll hold it, what the money should do, your next renewal and your business can each outweigh a fraction of a percentage point. We ask about those five things first, show you the mortgage side of the arithmetic, and leave investment and tax decisions to your financial advisor and your accountant.
Why the rate isn't all that matters
A mortgage costs you the interest for as long as you keep it. Any penalty to leave early, and the fees to set the mortgage up or move it, add to that cost. The rate drives the interest; the contract drives the penalty and the fees.
The clearest example is the prepayment penalty on a fixed mortgage. The fixed-rate penalty is usually the higher of three months' interest or the interest rate differential (IRD: your rate against the lender's current rate for the time left); lenders may work it out from posted rates, and your contract governs (source: Financial Consumer Agency of Canada, checked October 2026).
Two offers a fraction of a point apart can carry penalties thousands of dollars apart. If you sell or refinance mid-term, the smaller rate can cost more. Planning ahead works through an example.
What matters before talking about rate
- What is the property for? Lenders and insurers treat a home, a rental, a home with a rental unit and the security behind a business differently. For example, on a CMHC-insured mortgage for a two-unit home you live in, up to 100% of the gross rent may be added to your income, and a one-unit rental isn't eligible for mortgage loan insurance at all (source: CMHC, checked October 2026).
- How long will you hold the property? The term (how long this contract and rate last) and the time you'll own the home are different numbers. When the term ends you can renew, switch or pay off with no prepayment penalty; leaving earlier generally costs a penalty.
- What should the money do? Keep the payment small, pay the mortgage off sooner, keep room to borrow again, or take equity out. Each goal points to a different amortization (the total time to pay the loan off), different prepayment privileges and a different kind of loan.
- What happens at the next renewal? Since November 21, 2024, OSFI does not expect lenders to apply the stress test when an uninsured mortgage moves to another federally regulated lender at renewal, as long as the amount and the amortization don't increase (source: OSFI, checked October 2026). A plan that keeps you able to switch keeps your next renewal a real negotiation.
- What does the business need? If you are self-employed, how you are paid shapes the income lenders generally see.
The four most common situations requiring mortgage strategy
Most of the questions people bring us come from one of four situations. Each guide below has the questions people in that situation ask, a tool that puts your own numbers on it, and what we do next.
You own your home, and your plans may change before the term ends
Does the lower mortgage rate always cost less? Planning ahead in OntarioFor an Ontario homeowner, a lower rate costs less only if the rest of the contract fits how long you'll keep the home. Term, penalty and portability decide it.
You're self-employed or paid through your own company
Higher profitability, not just approval: self-employed mortgages in OntarioYour accountant decides salary, dividends and incorporation. We show how lenders generally read the result for your mortgage.
You're moving, separating, inheriting a home, rebuilding after a consumer proposal or closing on a new build
Life events and your mortgage in Ontario: moving, separation, inheritance and moreIn Ontario, buying before selling, separation, a consumer proposal, an inheritance or a pre-construction closing turn on timing and qualifying, not the rate.
You're buying a rental, renting out a unit in your home, or adding a property
More money, structured right: rental and investment mortgages in OntarioFinancing a rental in Ontario turns on how lenders count the rent, whether the property carries itself, and what happens when a bank reaches its limit.
The three rules on investment returns, tax advice and lender approval when it comes to your mortgage
No investment returns. We don't forecast markets, investments or property values, so we never show "invest the difference" with a return figure attached. Whether to invest or pay the mortgage down depends on those returns, so the choice is a question for your financial advisor. We show the mortgage half only: payments, interest, the balance left, and any penalty.
No tax advice. Tax decisions are for your accountant: salary or dividends, whether to incorporate, whether interest is deductible, capital gains on a sale, and HST on a new build. We show how lenders generally read the result and what it means for the mortgage.
The lender decides. Anything we set out is subject to lender approval.
What we do with your plan
Bring your plan, not just your letter. We talk about structure before price. Tell us what the property is for, how long you expect to keep it, and what you want the next five years to look like.
We set out the choices that follow: term, amortization, prepayment privileges, portability, fixed or variable. Then we compare what the banks, credit unions and monoline lenders (mortgage-only lenders without branches) we work with would offer for that structure, subject to lender approval.
When the plan says the mortgage you have, or the renewal your bank has offered, already fits, we say so.
Sources
- Financial Consumer Agency of Canada — Mortgage fees: Prepayment penalties, page dated 2025-10-15, checked 2026-10-26.
- OSFI — Straight switches exempt from the minimum qualifying rate, effective 2024-11-21, checked 2026-10-23.
- CMHC — Rental Income, published 2024-05-22, checked 2026-10-26.
What to do next
Pick the hub that fits your plan, or try the total cost of holding tool on your own numbers. To talk it through with a person, use the call-back form.
Common follow-up questions
Does a smaller rate always mean the mortgage costs less?
No. Over a full term with no changes, a smaller rate generally costs less. If you sell, move or refinance before the term ends, a stricter penalty method or smaller prepayment privileges can outweigh the saving. The total cost of holding tool puts two scenarios side by side on your numbers. Results are estimates only, not an offer or advice.
Will you tell me whether to invest or pay down my mortgage?
No. The invest-or-prepay comparison depends on investment returns we do not forecast, so it belongs with your financial advisor. We can show the mortgage side: how much interest a prepayment saves and what the balance would be at renewal. The prepayment savings tool does that arithmetic.
Do I need a written plan before I talk to you?
No. A rough answer to "how long will I keep this, and what is it for" is enough to start. If you already have a renewal letter or refinance quote from your bank, bring it too: can your bank do better? checks it.
This page is general information for Ontario readers, not financial, legal or tax advice. Public rules on this page were checked on 2026-10-26; your mortgage contract governs. Every mortgage is subject to lender approval.