Household mortgage stress test: would your cash survive?
The lender's stress test checks whether you could carry your mortgage at a higher rate on paper. This tool runs your real monthly cash through a renewal 1 to 3 points higher, a lost income and a surprise bill, shows the month your savings would run out, and solves what would carry you through.
Household stress test
Your real monthly cash, run through rate, income and expense shocks. Example values; replace them with yours. Nothing leaves your browser.
- Monthly cushion today
- $373
- left after every bill
- Payment today
- $2,877
- at 4.58%
- If you renew 2 points higher
- $3,367
- +$490 a month
- Lowest cash, worst case
- -$8,499
- month 11
Estimate, not advice. Educational estimate only, not financial, mortgage, tax or legal advice. Lenders, insurers and governments set their own rules and can change them; confirm with a licensed professional before you decide.
2 of 7 shocks run your cash below zero. Worst: One income lost for 6 months (half of take-home).
The shock deck
Choose a row to solve its recovery levers.
| Scenario | Payment after renewal | Lowest cash | Runs out |
|---|---|---|---|
| $2,877 | $15,000 | No | |
| $3,118 | $15,000 | No | |
| $3,367 | $15,000 | No | |
| $3,625 | $10,413 | No | |
| $2,877 | -$8,499 | Month 9 | |
| $2,877 | $2,237 | No | |
| $3,367 | -$6,339 | Month 36 |
What would carry you through: one income lost for 6 months (half of take-home)
About $8,500 more in savings before the shock.
Spend $780 a month less, starting now.
A lump sum of $129,000 from outside cash (a gift, a bonus) lowers the renewal payment enough. Check your prepayment privileges.
Stretching to 30 years doesn't cover it on its own.
Show the numbers
| Month | Nothing goes wrong | Renew 2 points higher | One income lost for 6 months |
|---|---|---|---|
| 3 | $16,118 | $16,118 | $16,118 |
| 6 | $17,237 | $17,237 | $12,637 |
| 9 | $18,355 | $18,355 | -$45 |
| 12 | $19,473 | $19,473 | -$8,127 |
| 15 | $20,592 | $20,592 | -$7,008 |
| 18 | $21,710 | $21,710 | -$5,890 |
| 21 | $22,828 | $22,828 | -$4,772 |
| 24 | $23,947 | $23,947 | -$3,653 |
| 27 | $25,065 | $25,065 | -$2,535 |
| 30 | $26,183 | $26,183 | -$1,417 |
| 33 | $27,302 | $25,832 | -$298 |
| 36 | $28,420 | $25,480 | $820 |
| 39 | $29,538 | $25,129 | $1,938 |
| 42 | $30,657 | $24,777 | $3,057 |
| 45 | $31,775 | $24,425 | $4,175 |
| 48 | $32,893 | $24,074 | $5,293 |
| 51 | $34,012 | $23,722 | $6,412 |
| 54 | $35,130 | $23,371 | $7,530 |
| 57 | $36,248 | $23,019 | $8,648 |
| 60 | $37,367 | $22,668 | $9,767 |
| 63 | $38,485 | $22,316 | $10,885 |
| 66 | $39,603 | $21,964 | $12,003 |
| 69 | $40,722 | $21,613 | $13,122 |
| 72 | $41,840 | $21,261 | $14,240 |
Assumptions & sources
Assumptions
- Month 1 is next month. Cash = today's cash + take-home income − mortgage payment − housing costs − other spending − debt payments, month by month.
- Fixed-rate payments with semi-annual compounding. At renewal the payment is recalculated on the remaining balance and remaining amortization at the new rate.
- Shocks are examples, not forecasts: renewal at +1, +2 and +3 points, half of take-home income lost for 6 months, a $15,000 one-time cost, and a +2-point renewal followed by an income loss.
- Extending the amortization at renewal, or prepaying, may count as new lending: a lender can requalify you at the stress-test rate. Income taxes, benefits and EI are not modelled.
Sources
- OSFI — Minimum qualifying rate for uninsured mortgages (effective January 29, 2026). Checked .
- Justice Laws — Interest Act, R.S.C. 1985, c. I-15, s. 6. Checked .
| Mortgage | $480,000 at 4.58%, 22 years left, renewing in 30 months |
|---|---|
| Take-home income | $9,200 a month |
| Housing costs, other spending, debts | $650, $4,900, $400 |
| Cash on hand | $15,000 |
| Payment today vs after renewal | $2,877 vs $3,367 |
| Lowest cash | -$6,339Month 72 |
| Cash runs out in month 36 | Fix: about $6,400 more saved, or $90 a month less spending |
This household passed the lender's stress test when it bought. The ledger shows the other question: whether its cash survives if a higher renewal and a lost income arrive back to back.
Open this example in the calculator →Computed November 1, 2026.
How this calculator works
The tool keeps a monthly ledger: cash on hand, plus take-home pay, minus the mortgage payment, housing costs, other spending and debt payments. At renewal it recalculates the payment on the balance you'll still owe, over the years left, at the new rate. Each scenario changes one thing (or two, for the combined case) and runs the same ledger for at least six years.
For the scenario you pick, it then solves four levers on their own: how much more cash you'd need saved, how much less you'd need to spend each month, how big a prepayment before renewal would do it, and how many years you'd need to add at renewal. Adding years or money at renewal can count as new lending, so a lender may apply the stress test to it. For the payment-change question alone, RateChange.ca goes deeper on renewal payment shock.
Frequently asked questions
How is this different from the mortgage stress test?
The lender's stress test is a qualification rule: it checks your ratios at the qualifying rate before you borrow. This tool asks what actually happens to your monthly cash if rates rise at renewal or your income drops, and how long your savings would last.
What does 'renew 2 points higher' mean?
Your new term's rate is 2 percentage points above today's. That's the size of the stress-test buffer: the lender checked you could afford it on paper; this shows whether your budget agrees.
Should I extend my amortization at renewal?
It lowers the payment but costs more interest, and a longer amortization is usually treated as new lending, so the lender can requalify you. Compare it with the other levers the tool solves.
Primary sources
- OSFI — Minimum qualifying rate for uninsured mortgages (effective January 29, 2026). Checked .
- OSFI — Final revised Guideline B-20 (letter of October 17, 2017) (effective October 17, 2017). Checked .
- Justice Laws — Interest Act, R.S.C. 1985, c. I-15, s. 6. Checked .