The client
A household in St. Catharines-Niagara had the income for a $450,000 purchase at 10% down, but a $640-a-month vehicle loan and three credit cards carrying $18,000 combined pushed the file past CMHC’s TDS maximum before any restructuring.
Combined income
$9,000/mo
$108,000/yr
Property
$450,000 home, St. Catharines-Niagara
10% down payment
Vehicle loan
$640/mo
Paid off entirely as part of the restructure
Credit cards
$18,000 across three cards
Paid down to $9,000
The problem
GDS on its own was fine at 36.9%. TDS was not.
The before-restructure arithmetic
- ▸Housing costs: qualifying payment $2,871 + property tax $340 + heat $110 = $3,321/mo
- ▸Card minimum-payment convention: 3% of the $18,000 combined balance = $540/mo
- ▸TDS: ($3,321 + $640 vehicle + $540 cards) ÷ $9,000 = 50.0% — against CMHC’s 44% maximum. Declined.
None of the individual debts was unusual on its own, and none would look out of place against Canada’s household debt service ratio. Together, on top of an otherwise ordinary insured purchase, they added ten points of TDS the file didn’t have room for.
The numbers
At 10% down this is an insured mortgage, so GDS 39% and TDS 44% are hard maximums.
| Structuring the insured loan | Amount |
|---|---|
| Purchase price | $450,000 |
| Down payment (10%) | −$45,000 |
| Base mortgage (90% LTV) | $405,000 |
| CMHC premium — 3.10% in the 85.01–90% LTV band, capitalized | +$12,555 |
| Total insured mortgage | $417,555 |
| Rate & payments | Figure |
|---|---|
| Contract rate (illustrative, not a quote) | 4.79% |
| Minimum qualifying rate | 6.79% |
| Monthly P&I at the qualifying rate | $2,871 |
| Monthly P&I at the contract rate | $2,379 |
GDS — never the issue
| GDS | Monthly |
|---|---|
| P&I at the qualifying rate | $2,871 |
| Property tax | $340 |
| Heat (lender-standard estimate) | $110 |
| Housing costs $3,321 ÷ income $9,000 → GDS 36.9% — under 39% | ✓ |
TDS — before and after the restructure
| TDS line | Before | After |
|---|---|---|
| Housing costs (GDS numerator) | $3,321 | $3,321 |
| Vehicle loan | $640 | paid off |
| Credit-card minimum payment (3% convention) | $540 (on $18,000) | $270 (on $9,000) |
| TDS vs. the 44% cap | 50.0% ✗ | 39.9% ✓ |
The solution
An FSRA-licensed Ontario mortgage agent laid out the restructure with the client before submitting anywhere: pay off the vehicle loan outright, and apply $9,000 toward the credit cards to cut the balances in half.
Both moves came from funds the client already had earmarked for other uses, redirected once the ratio math showed exactly what each dollar of paydown was worth in TDS. A debt-consolidation refinance was considered and set aside — it would have added its own closing costs to a file that didn’t need a bigger loan, just a lighter one.
The submission went in with proof of both payoffs: the vehicle loan’s discharge statement and updated card statements showing the reduced balances, so the lender was underwriting the after-restructure file, not taking the client’s word for it.
The outcome & the closing math
Approved and funded: insured at 90% LTV, 25-year amortization, 5-year fixed term. TDS moved from 50.0% to 39.9% — comfortably under the 44% maximum, and with headroom the pre-restructure file never had.
| Cash due at closing (beyond the down payment) | Amount |
|---|---|
| Ontario land transfer tax on $450,000 — 0.5% / 1.0% / 1.5% marginal brackets | $5,475 |
| Ontario RST on the insurance premium — 8% × $12,555; the premium itself is capitalized, but the tax on it is cash at closing | $1,004 |
| Legal fees, title insurance & adjustments | varies |
What to take from this file
- 01Small recurring debts compound in the TDS calculation. A vehicle loan and a handful of credit cards, none large on its own, added ten points of TDS together.
- 02The minimum-payment convention on revolving debt is a policy choice, not a fixed rule. The 3%-of-balance figure used here is illustrative; each lender sets its own.
- 03Paying down a balance is often cheaper than adding a bigger loan. A debt-consolidation refinance was on the table and set aside once a simple paydown solved the ratio on its own.
- 04Prove the restructure, don’t just describe it. Discharge and statement evidence let the lender underwrite the after-picture with confidence.
Sources
Every regulatory figure in this file traces to one of these primary sources. Client details and anything that varies by lender are illustrative, as flagged below.
- ▸CMHC — Purchase (Mortgage Loan Insurance) — default-insurance premium schedule by LTV band (25-year amortization).
- ▸CMHC — CMHC Home Start — minimum down payment tiers (5%/10%) and the $1.5M insured price cap.
- ▸OSFI — Minimum qualifying rate for uninsured mortgages — the minimum qualifying rate — greater of contract rate + 2% or 5.25%.
- ▸CMHC — CMHC Reviews Underwriting Criteria — GDS 39% / TDS 44% maximums and the 600 credit-score floor for insured files.
- ▸Ontario.ca — Retail Sales Tax: Insurance and Benefits Plans — 8% Ontario RST on default-insurance premiums, cash at closing.
- ▸Ontario.ca — Calculating Land Transfer Tax / Land Transfer Tax Refunds for First-Time Homebuyers — Ontario's marginal land transfer tax brackets and first-time-buyer refund.
- ▸Provincial/territorial mortgage-broker legislation fetched directly (bclaws.gov.bc.ca, legisquebec.gouv.qc.ca, fcaa.gov.sk.ca, web2.gov.mb.ca, nslegislature.ca, assembly.nl.ca) plus FCNB's own site for NB and CanLII's index for PE — see notes for per-province method — provincial mortgage regulators and licence titles.
Illustrative in this file — lender-specific, not rules:
- ▸4.79% contract rate — rates move daily; not a quote.
- ▸3%-of-balance minimum-payment convention — the percentage used for revolving debt with no fixed payment varies by lender.
Authority & provenance
How this case file was built
We publish the origin, the verification method and the reviewer for every case file, so you can judge how far to trust it before you rely on it with a client.
Where it comes from
Derived from files handled by Treadstone’s fulfillment desk and from scenarios contributed by partner brokerages. Names, employers, exact amounts and dates are changed so no client or file is identifiable.
Provenance: Composite — a pattern seen repeatedly on fulfilled files, not a single transaction.
What is verified
Every regulatory figure traces to a primary source listed above and was checked against it on the date shown. The arithmetic is recomputed by machine on every rebuild.
Anything that varies by lender is labelled illustrative rather than stated as a rule.
Who reviewed it
Reviewed for Canadian regulatory accuracy before publication, and re-checked whenever a cited rule changes.
Reviewed by: Nicholas Parson, Treadstone Associates — reviews every case file before publication.
This case file is professional reference material for licensed mortgage professionals. It is not advice to a borrower, and it is not a lender commitment. Insurer rules, qualifying rates and provincial taxes change — confirm the current position with the insurer, regulator or lender before you rely on any figure here in a live file.