What this calculator answers
Amortization is the number of years it would take to pay off the mortgage at today's payment. Stretching it from 25 to 30 years lowers each payment, but you pay interest for five more years, and you pay down the balance more slowly in every term. With less than 20% down, a 30-year amortization also costs a bit more in insurance and is only available to first-time buyers and buyers of newly built homes.
The third column shows a middle path: take 30 years for flexibility, but pay the 25-year amount when you can.
How the calculation works
- Mortgage = price − down payment + any insurance premium. The 30-year option adds the 0.20 point surcharge to the premium rate when insured.
- Payments and interest are simulated month by month with Canadian compounding: semi-annual for fixed rates, and the compounding you choose for variable.
- Term figures show the interest paid and the balance at your first renewal. Full-amortization figures assume the rate never changes.
Assumptions and limits
- The 25-year insured limit and the 30-year exception for first-time buyers and new builds are federal rules. For uninsured mortgages, the maximum amortization is set by the lender.
- The insurance surcharge is insurer pricing, as listed in our sources.
- The rate stays the same for the whole amortization. That is never true in practice, so treat lifetime interest as a comparison, not a forecast.
- Prepayment limits, penalties and lender rate differences for 30-year amortizations are not modelled unless you enter a different 30-year rate.
Common questions
Is a 30-year mortgage a bad idea?
Not necessarily. It costs more interest if you only make the minimum payment, but the lower required payment gives you breathing room. Many people take 30 years and make extra payments when they can.
Who can get a 30-year amortization in Canada?
With 20% or more down, most lenders offer it. With less than 20% down (an insured mortgage), only first-time buyers and buyers of newly built homes, since December 15, 2024.
Can I switch from 30 to 25 years later?
Yes. At renewal you can choose a shorter amortization, and during the term you can shorten it with prepayments. Lengthening it later usually means qualifying again, as with a refinance.
Does a 30-year amortization help me qualify?
Usually yes, because the stress test payment is lower. Try both in the affordability calculator.
Sources
- CMHC notice, premiums and 30-year amortization (rules checked 2026-10-31)
- Ratehub: PST on CMHC insurance by province (rules checked 2026-10-31)
- Interest Act, section 6 (rules checked 2026-10-31)
- OSFI: minimum qualifying rate (rules checked 2026-10-31)