IF the mortgage is insured through CMHC or Genworth Financial, GDS and TDS are calculated on the total loan amount, including the Mortgage Insurance premium.

Various maximum allowable GDS and TDS ratios are considered by different lenders and even with the same lender, various ratios will apply for different clients with different credit history.

For this reason it is important to speak to a knowledgeable independent mortgage professional, who will be able to quickly determine whether or not one will qualify for a mortgage with a particular lender.

Total Debt Service (TDS) ratio:

= PITH (principal + interest + property taxes + heat) + 50% of condo fees (if applicable) + payments on all debts
Gross annual household income

Gross Debt Service (GDS) ratio:

= PITH (principal + interest + property taxes + heat) + 50% of condo fees (if applicable)
Gross annual household income