The client
A dentist practising through her own professional corporation wanted to move up to a larger home in Mississauga, part of the Toronto market. Like many incorporated professionals, she pays herself a modest T4 salary and leaves most of the practice’s earnings inside the corporation for tax planning — which is exactly what made her first attempt at qualifying fail badly.
Personal T4 salary
$48,000/year
From her own professional corporation
Corporate net income
$185,000 (yr 1), $225,000 (yr 2)
Two-year corporate financials and NOAs
Retained earnings
$260,000 on the balance sheet
Confirms the income being grossed up actually exists
New purchase
$1,150,000 Mississauga move-up home
20% down, conventional
Existing debt
Vehicle lease, $520/mo
No other consumer debt
The problem
A generalist lender reviewed the file the way it reviews any T4 employee: personal income only. On a $48,000/year salary ($4,000/mo), the $1,150,000 purchase was never close.
The T4-only arithmetic
- ▸Qualifying payment at the stress-tested rate: $6,359/mo
- ▸Against $4,000/mo in T4 income
- ▸Gross debt service ratio: 179.0%. Not a marginal decline — the file simply was not reviewed as an incorporated professional’s income at all.
The T4 salary was never meant to represent her full economic capacity — it is a tax-planning number, not an income number. The practice’s corporate financials told a very different story.
The numbers
The purchase is conventional at 20% down, so no default-insurance premium applies. The work here is entirely on the income side.
| Grossing up the corporate income | Amount |
|---|---|
| Corporate net income, year 1 | $185,000 |
| Corporate net income, year 2 | $225,000 |
| Two-year average | $205,000/year |
| Grossed up 15% (lender's published add-on) | $235,750/year |
The corporation’s $260,000 in retained earnings comfortably covers the $235,750 being grossed up — the lender required this confirmation as proof the income actually exists and could be withdrawn, not just projected from a formula.
| Income used | Monthly |
|---|---|
| T4 salary | $4,000 |
| Grossed-up corporate share | $19,646 |
| Combined qualifying income | $23,646 |
GDS and TDS, two ways
| Rate & payments | Figure |
|---|---|
| Contract rate — 5-year fixed (illustrative, not a quote) | 4.85% |
| Minimum qualifying rate | 6.85% |
| Monthly P&I at the qualifying rate | $6,359 |
| Ratio | T4 only | Grossed up |
|---|---|---|
| GDS | 179.0% ✗ | 30.3% ✓ |
| TDS | 192.0% ✗ | 32.5% ✓ |
Ontario land transfer tax on the $1,150,000 purchase comes to $19,475 — Mississauga levies no municipal land transfer tax of its own (unlike Toronto), so only the province’s marginal brackets apply, with no first-time-buyer refund since this is a repeat, move-up purchase.
The solution
An FSRA-licensed Ontario mortgage agent rebuilt the income case from the corporate financials up.
First, built a two-year average of corporate net income from the practice’s financial statements and Notices of Assessment, the same underlying discipline covered in our walkthrough of calculating self-employed income from a T1 and T2.
Second, applied the lender’s published gross-up convention — a 15% add-on reflecting that a dollar taxed at the small-business corporate rate is not directly comparable to a dollar of personal income — and confirmed against the corporation’s balance sheet that the retained earnings actually support the income being claimed. The pattern of an incorporated borrower using retained earnings to qualify is the same one covered in our incorporated-retained-earnings walkthrough.
The outcome & the closing math
Approved and funded: conventional at 80% LTV, 25-year amortization, on a 5-year fixed term.
| Cash due at closing (beyond the down payment) | Amount |
|---|---|
| Ontario land transfer tax on $1,150,000 — provincial marginal brackets only; Mississauga has no municipal land transfer tax | $19,475 |
| Legal fees, appraisal & adjustments | varies |
What to take from this file
- 01A T4-only review of an incorporated professional understates income by design. Leaving earnings in the corporation is a deliberate tax strategy, not evidence of low income.
- 02The gross-up percentage is lender policy, not a rule. Shop it — 15% here, but every lender publishes its own convention.
- 03Retained earnings on the balance sheet is the proof the income exists, not just a formula input — always confirm the corporation can actually fund what is being grossed up.
- 04Budget the land transfer tax even on a move-up purchase. There is no first-time-buyer refund for repeat buyers, and municipal-versus-provincial-only tax depends on the specific municipality, not the region’s name.
- 05The qualifying-rate math on a mortgage this size moves fast. Confirm the numbers before setting price-range expectations with an incorporated client.
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.
- ▸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 — 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:
- ▸4.85% contract rate — rates move daily; not a quote.
- ▸15% gross-up add-on over the 2-year corporate average — each lender publishes its own gross-up convention for incorporated professionals.
- ▸2-year corporate-income averaging window — lender policy, not a regulatory requirement.
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.