What are the gross and total debt service ratios?
The gross debt service ratio (GDSR) is 1 of 2 calculations a mortgage provider uses to stress test your ability to pay shelter-related costs and determine how large a mortgage you can afford.
The GDSR is the percentage of your pre-tax income you’ll use to pay for housing costs including mortgage payments, heating costs, property taxes and if applicable, condo fees.
The second calculation is the total debt service ratio (TDSR) which includes all your outstanding personal debt (mortgage, car loans, credit card, lines of credit, etc.).
The acceptable GDSR and TDSR varies by mortgage provider. Most mortgage providers are looking for a maximum GDSR of 32% and a maximum TDSR of 40%. However, most borrowers with good credit and a reliable income will be allowed to exceed these guidelines.
How to calculate GDSR and TDSR
You can calculate your GDSR and TDSR using the following steps:
For GDSR
- Total your mortgage payments, property taxes, heating costs for one year and if applicable, 50% of your annual condo fees
- Divide this total by your annual pre-tax household income
- Multiply this number by 100 to get your GDSR
For TDSR
- Total your mortgage payments, property taxes, heating costs for one year and if applicable, 50% of your annual condo fees
- Add your total debt payments for all other loans and credit cards for one year.
- Add the sums in steps 1 and 2 together.
- Divide this total by your annual pre-tax household income
- Multiply this number by 100 to get your TDSR
What a high GDSR/TDSR means
A high GDSR and TDSR ratio (close to the maximum or over) may not disqualify you from getting approved for a mortgage. However, you may have to reconsider the cost of the home you can afford, or if there are other monthly expenses you could reduce like loans or your credit card balance.
A GDSR and TDSR below the maximum means you should comfortably afford your mortgage and associated home ownership costs and could potentially afford a more expensive property.