Canada Mortgage Qualifier & CMHC Insurance Method, Formula & Examples
On this page
This method guide explains the calculation sequence behind the Canada Mortgage Qualifier & CMHC Insurance Calculator. It owns formulas, input definitions, timing, rounding and reference checks; the calculator remains the only page that performs the numeric scenario.
Calculation sequence
The model applies the current CMHC owner-occupied premium bands when LTV exceeds 80%, adds the premium to the mortgage, converts the qualifying nominal rate from semi-annual compounding and calculates GDS and TDS.
Inputs and evidence
Use current written documents for every material input. The calculator supports: Market and currency, Purchase price, Down payment, Down-payment type, Contract nominal rate, Amortization, Gross household annual income, Annual property tax, Monthly heating cost, Monthly condominium fees, Other monthly debt payments.
Reference example
A 500,000 purchase with 100,000 down has 80% LTV, so this worksheet adds no CMHC premium. Qualification still uses the greater of the contract rate plus 2% or 5.25%.
Boundary and error checks
Test zero-rate branches where available, minimum and maximum supported inputs, and a scenario in which the main result reverses. Reject blank, non-finite or out-of-range values rather than silently substituting them.
Model boundary
This tool does not determine approval, credit, insurer eligibility, minimum down payment, provincial premium tax, rental treatment, property eligibility or exceptions. Rules checked 2026-10-08.
Sources and review status
- CMHC — Mortgage loan insurance cost
- OSFI — Minimum qualifying rate for uninsured mortgages
- FCAC — Mortgage Qualifier Tool
Sources and model boundaries checked 2026-10-08. This new opportunity-map expansion has automated formula, fixture and source QA but has not been represented as human editorial review. Keep the route noindex until CalculatorGeek records a completed YMYL editorial review.