Debt-to-income ratio explained for Canadian borrowers

A debt-to-income ratio compares your regular debt payments with your gross income.

By Promissory.ca Editorial Team Reviewed against official Canadian sources Last updated: 2026-09-16

What a debt-to-income ratio is

A debt-to-income ratio compares how much you owe in regular payments with how much you earn. Lenders use it as a quick measure of whether there is room in your budget for another payment. It is not the only thing they look at, but it is one of the most important.

The idea is simple. Two people can owe the same amount but be in very different positions, depending on what they earn. A ratio captures that difference in a single number.

How the ratio is calculated

The basic formula is your total monthly debt payments divided by your gross monthly income, then multiplied by 100 to express it as a percentage.

Gross income means your income before tax and other deductions. Debt payments usually include minimum credit card payments, instalment loan payments, car loan payments, and housing costs where the lender counts them. Some lenders also include child support and other fixed obligations.

Because each lender defines income and debt slightly differently, the same borrower can be given a different ratio by different lenders. That is one reason a decline from one lender does not necessarily mean every lender will decline you.

What counts as income and what counts as debt

Why lenders care

A ratio tells a lender how much of your income is already committed. A borrower with a low ratio has more room to absorb a new payment and to cope with a change in circumstances. A borrower with a high ratio is stretched, and a small shock such as a job loss or a car repair could push them into missed payments.

That is why lenders often ask for proof of income and a list of your existing obligations. They are not only checking whether you can pay today. They are estimating whether you can keep paying if something changes.

Why two borrowers with the same income differ

Income is only half the picture. A borrower who carries a large car loan and several credit cards may have a much higher ratio than a neighbour earning the same salary with only a modest mortgage. That is why lenders ask about your obligations in detail rather than looking at your salary alone. It also explains why paying down a balance can improve your position even when your income has not changed.

Lenders also look at how long you have held your accounts and whether your payments arrive on time. A steady record can offset a ratio that looks high on paper, while a recent missed payment can work against a lower one.

Mortgages use two ratios

Mortgage lenders in Canada often look at two ratios rather than one. The first compares housing costs alone with income. The second compares housing costs plus all other debt payments with income. The second is broader and is usually the one that decides how much you can borrow.

Federally regulated lenders also apply a stress test, which checks whether you could still afford the payments at a higher qualifying rate than the one you are being offered. The stress test is designed to make sure you are not borrowing right at the edge of what you can manage. It applies even when your actual contract rate is lower.

How to lower your ratio

1. Pay down the balances with the highest interest first, which reduces both the balance and the minimum payment.
2. Avoid taking on new credit before an important application such as a mortgage.
3. Increase your income where you can, through extra hours, a raise or a side income.
4. Consolidate high-interest debts into a single lower payment, if it genuinely reduces the total cost.
5. Reduce recurring obligations where possible, such as an unused subscription or a lease you can end.
6. Check your credit report for errors that could be inflating the debts a lender sees.

A ratio is a snapshot, not a verdict

A single ratio does not decide your future. Lenders also weigh your credit history, the size of your down payment, the type of loan, and how stable your income is. A borrower with a modest ratio but a thin credit file may be treated differently from one with a higher ratio but a long record of on-time payments.

What the ratio does give you is a tool. Working it out for yourself before you apply helps you see where you stand and what would improve your position. If the number is higher than you expected, that is useful information, not a final answer.

How to calculate your own ratio

1. Add up your gross monthly income from all sources you can document.
2. Add up every monthly debt payment, using minimums for revolving credit.
3. Divide the debt total by the income total.
4. Multiply by 100 to get a percentage.
5. Repeat the exercise using only housing costs if you are preparing for a mortgage.

Your data and your application

When you apply, the lender collects income and debt information. In Canada, that handling is governed by the Personal Information Protection and Electronic Documents Act (PIPEDA). You have the right to know why information is collected, to access it, and to ask for corrections.

Where Promissory.ca fits

Promissory.ca is not a lender, a credit counsellor or a Licensed Insolvency Trustee. We do not make lending decisions and we do not charge you a fee. We publish plain-language information and calculators, and we may receive compensation from lending partners. Any decision about borrowing is yours, and you are never obligated to accept an offer.