Rates & comparisons
How the OSFI Stress Test and GDS/TDS Ratios Work in 2026, and When You Can Qualify Outside It
The stress test decides how much you can borrow, not what you pay. Here is the exact arithmetic, why Niagara property taxes move your limit, and the legitimate routes outside the federal test: straight switches and provincially regulated credit unions.
Reviewed November 13, 2026 · Indicative figures, OAC
The rule
Under OSFI's Guideline B-20, federally regulated lenders must qualify you at a minimum qualifying rate: the higher of 5.25% or your contract rate plus 2.00%. It applies to purchases and refinances. Insured mortgages (under 20% down) must meet the same test at every lender, because the default insurers require it. You still pay your contract rate; the stress test only sets the ceiling on what you can borrow.
- Qualifying rate
- Higher of 5.25% or rate + 2.00%
- Maximum GDS
- 39%
- Maximum TDS
- 44%
- Straight switch at renewal
- No stress test
| Mortgage | Contract rate | Qualifying rate |
|---|---|---|
| Insured 5-yr variable | 3.65% | 5.65% |
| Insured 5-yr fixed | 4.29% | 6.29% |
| Insurable 5-yr fixed | 4.39% | 6.39% |
| Uninsured 5-yr fixed | 4.54% | 6.54% |
| Any rate at or below 3.25% | ≤ 3.25% | 5.25% (floor) |
GDS and TDS, defined
GDS (gross debt service) = (principal and interest at the qualifying rate + property tax + heating + 50% of condo fees) ÷ gross monthly income.
TDS (total debt service) = everything in GDS + all other debt payments ÷ gross monthly income. Car loans and leases count at the actual payment, credit cards at 3% of the balance, and lines of credit at a qualifying payment (often 3% of the balance, or interest at the qualifying rate).
Insured files cap GDS at 39% and TDS at 44%, with at least one borrower holding a credit score of 600 or more. Most lenders apply similar limits to uninsured files. Notice what the formula rewards: a $5,000 credit-card balance costs $150 a month of TDS whether you pay it in full each month or not, so clearing it before you apply can add more borrowing room than a raise.
Why Niagara property taxes move your limit
Property tax sits inside GDS, and Niagara's approximate effective residential rates range from about 1.08% in Niagara-on-the-Lake to about 1.68% in Fort Erie. Same income, same debts, different town, different answer.
Worked example: one household, Grimsby vs Fort Erie
A couple earns $110,000 a year combined ($9,166.67 a month). They have a $450 car payment and a $5,000 credit-card balance (counted at $150), so $600 a month of other debts. They have $130,000 for a down payment (20%+), want a 25-year amortization, and are quoted the insurable 5-year fixed at 4.39%, which means qualifying at 6.39%. We assume $150 a month for heating, and use Grimsby's approximate 1.15% and Fort Erie's approximate 1.68% tax rates.
| Item | Grimsby | Fort Erie |
|---|---|---|
| Maximum purchase price | $546,000 | $516,000 |
| Mortgage | $416,000 | $386,000 |
| Qualifying payment at 6.39% | $2,758.79 | $2,559.84 |
| Monthly property tax | $523.25 | $722.40 |
| GDS | 37.44% | 37.44% |
| TDS (the binding limit) | 43.99% | 43.99% |
Grimsby check: GDS = ($2,758.79 + $523.25 + $150) ÷ $9,166.67 = 37.44%; TDS adds the $600 of debts for 43.99%. Fort Erie's higher tax rate eats $199.15 a month of the same budget and cuts the maximum price by about $30,000. Their actual payment on the $416,000 Grimsby mortgage at 4.39% would be $2,277.08, about $482 below the qualifying payment.
Check the tax rate for the specific town in our community guides, and always confirm with the municipality's current tax rates before you write an offer.
Qualifying outside the federal stress test, legitimately
There is no trick to the stress test, but there are situations it does not cover, and lenders it does not bind. These are the routes we use, all of them fully disclosed and documented.
1. A straight switch at renewal
Since November 21, 2024, moving an uninsured mortgage to a new lender at renewal, with the same balance and the same remaining amortization, does not require passing the stress test. Insured mortgages were already exempt. For Niagara households who bought or refinanced at low rates and now struggle to requalify, this opens the full market at renewal instead of leaving you stuck with your current lender's offer. Adding money or amortization means full requalification. See our renewal and switch guide.
2. A provincially regulated Ontario credit union
Ontario credit unions are regulated by the province and are not bound by OSFI B-20. Some offer qualifying at the contract rate, or with extended ratios, on certain uninsured products (20%+ down) held on their own books. Policies vary by credit union and change, so we confirm them product by product.
| Item | Grimsby | Fort Erie |
|---|---|---|
| Maximum price at 6.39% (federal test) | $546,000 | $516,000 |
| Maximum price at 4.69% (contract-rate qualifying) | $608,000 | $570,000 |
| Qualifying payment at 4.69% | $2,696.32 on $478,000 | $2,481.97 on $440,000 |
Qualifying is not the same as affording. A higher limit at a higher rate (the credit-union tier is 4.69% against 4.39% insurable this week) means a bigger, more expensive mortgage; make sure the real payment fits your budget. More in monoline vs credit union.
3. Alternative lenders and private funds, with care
Federally regulated B-lenders still apply the minimum qualifying rate, but some accept higher ratios (in the 45%–50% range on certain products) and alternative proof of income, which helps self-employed borrowers. Private lenders and MICs are not bound by B-20 and lend mainly on equity, at 8.99%–12.99% plus fees. Both are short-term tools with an exit plan. See A vs B vs private.
Other honest levers
- Pay off or pay down revolving debt before applying.
- Choose a 30-year amortization if eligible; see 30-year amortization rules.
- Add a co-borrower or guarantor who genuinely shares the obligation.
- Include legal rental income from a secondary suite; see secondary suite mortgages.
Check your own numbers
- Gather gross income (T4s, or two years of tax returns and notices of assessment if self-employed).
- List every monthly debt, including 3% of each credit-card balance.
- Pick the town and use its approximate tax rate.
- Run the stress test in the affordability and stress test calculator.
- Get a pre-approval with a rate hold of up to 120 days, lender-dependent, on our pre-approval page.
Frequently asked questions
What is the mortgage stress test rate in 2026?
The minimum qualifying rate is the higher of 5.25% or your contract rate plus 2.00%. With this week's insured 5-year fixed at 4.29%, you qualify at 6.29%; with the insured 5-year variable at 3.65%, you qualify at 5.65%.
What are the maximum GDS and TDS ratios?
For insured mortgages, GDS can be up to 39% and TDS up to 44% of gross income, with at least one borrower scoring 600 or higher. GDS covers the qualifying mortgage payment, property tax, heating and half of any condo fees; TDS adds all other debt payments.
Do I need to pass the stress test to switch lenders at renewal?
Not on a straight switch. Since November 21, 2024, an uninsured mortgage moved to a new lender at renewal with the same balance and remaining amortization does not require the stress test, and insured mortgages were already exempt. Adding money or amortization requires full requalification.
Can I avoid the stress test with a credit union?
Ontario credit unions are provincially regulated and not bound by OSFI B-20, so some qualify certain uninsured mortgages (20%+ down) at the contract rate or with extended ratios. Insured mortgages must still meet the federal qualifying rate at any lender. Policies vary, so confirm the specific product's rules in writing.
Why does property tax affect how much I can borrow?
Property tax is part of GDS and TDS. In our example, a household earning $110,000 qualifies for about $546,000 in Grimsby at an approximate 1.15% tax rate but about $516,000 in Fort Erie at an approximate 1.68% rate, because the higher tax uses up more of the allowed ratio.
Pre-approval & rate review
Get your Niagara mortgage numbers checked
Tell us where you are buying or what you owe. We reply by email, usually within one business day, with options from across the lender tiers.
- A licensed advisor reviews your numbers against A-lenders, Ontario credit unions and alternative lenders.
- Rate holds of up to 120 days on purchases and renewals (lender-dependent).
- On prime files the lender pays the brokerage, so there is no fee to you; any fee on alternative or private files is disclosed in writing first.
- Nothing goes to a lender or credit bureau until you say so.
Prefer email? Write to hello@mortgageniagara.com.