What this calculator answers
If you put less than 20% down, your mortgage must have default insurance. It protects the lender, not you, but you pay for it. The premium is a percentage of the mortgage, set by your loan-to-value: the smaller your down payment, the higher the rate. It is normally added to your mortgage, so you pay interest on it too.
CMHC is the best-known insurer, and the two private insurers use the same rates for standard purchases. This calculator shows your premium, the full cost over the life of the mortgage and any provincial tax you would pay in cash.
How the calculation works
- Loan-to-value = (price − down payment) ÷ price.
- Premium = mortgage before insurance × the rate for your loan-to-value band. A 30-year amortization adds 0.20 percentage points.
- Total mortgage = mortgage before insurance + premium.
- Provincial tax = premium × the province's rate (Ontario 8%, Quebec 9%, Saskatchewan 6%, Alberta none). It is paid at closing.
- Payment impact compares the payment with and without the premium at your rate, using semi-annual compounding.
Assumptions and limits
- Premium rates and the 30-year surcharge are insurer pricing (CMHC, matched by the private insurers), not law. They can change.
- The minimum down payment and the $1.5 million price cap for insured mortgages are federal rules.
- Non-traditional down payments (for example borrowed funds), portability and top-up premiums are not modelled.
- Provincial tax rates are for Alberta, Ontario, Quebec and Saskatchewan only.
Common questions
Can I pay CMHC insurance upfront instead?
You can usually pay it in cash, but most buyers add it to the mortgage. Paying upfront saves the interest on it, at the cost of using cash you might need for closing.
Is CMHC insurance refundable if I sell?
No. Once the mortgage funds, the premium is not refunded. In some cases it can be transferred to a new mortgage when you move with the same lender; ask your lender.
Does a bigger down payment always save money?
Each step up in down payment moves you into a cheaper band, and at 20% the premium disappears. The table shows the premium on your price in each band, so you can see where an extra amount makes the biggest difference.
Do I pay tax on mortgage insurance in Alberta?
No. Alberta does not charge provincial tax on the premium. Ontario, Quebec and Saskatchewan do, and it must be paid in cash at closing.
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)