Treadstone Associates
Case File № 908 · Separation & Divorce

The tax nobody was flipping anything to owe

a St. Catharines-Niagara condo assignment after separation

A St. Catharines-Niagara couple's pre-construction condo was still a year from occupancy when they separated. Removing the departing spouse from the purchase agreement meant assigning her interest — and since 2022, federal law taxes every assignment sale, regardless of why it happens.

OntarioUninsured · PurchaseFiled August 11, 20265 min read
$22,000

paid to the departing spouse for her half-interest in the pre-construction unit

$2,860

GST/HST owing on that consideration — a 2022 rule neither spouse knew applied to them

39.0%

total debt service on the solo purchaser's completed closing

Anonymized illustration. The borrowers, dollar figures, and rates in this file are an illustrative composite — no real client is identifiable, and any rate shown is illustrative, not a quote. The rules are real: every regulatory figure is cited to its source in the Sources section, and the math computes exactly as shown.

№ 01

The client

A couple in St. Catharines-Niagara signed a $460,000 pre-construction condo Agreement of Purchase and Sale together in 2023, a year before occupancy — then separated while the building was still under construction.

Original agreement

$460,000, joint purchasers

St. Catharines-Niagara, signed 2023

Deposits paid to date

$46,000

10%, both spouses' funds

Paid to departing spouse

$22,000

For assigning her half-interest to the solo purchaser

Solo purchaser's income

$8,800/month

Qualifying alone for the first time

№ 02

The problem

Removing one joint purchaser from a pre-construction agreement and leaving the other to close alone is, in substance, an assignment of the departing spouse's interest — and since Budget 2022's amendment to the Excise Tax Act (enacted through the Budget Implementation Act, 2022, No. 1, in force for agreements entered into after May 6, 2022), every assignment sale of newly constructed or substantially renovated housing is taxable, regardless of the assignor's reason for assigning.

What CRA's GST/HST Notice 323 changed

  • Before May 2022, an assignment was only taxable if the assignor intended it as a resale for profit — a personal-use or family-reason assignment was generally exempt
  • Since then, the exemption is gone entirely: intent no longer matters, and a marriage breakdown gets no special treatment
  • A portion of the deposit repaid to the assignor can be excluded from the taxable consideration, but any amount paid beyond that — here, for the interest itself — is taxable

Neither spouse had budgeted for a tax bill on what felt like dividing their own property, not selling it to a stranger.

№ 03

The numbers

Once the taxable portion of the assignment was identified, funding it alongside the closing itself was straightforward arithmetic.

Closing the solo purchase and the assignment togetherAmount
Purchase price$460,000
Total down payment (20%, including the original deposit)−$92,000
Mortgage amount$368,000
Cash required at closingFigure
Additional down payment cash (20% total less the 10% deposit already paid)$46,000
Paid to the departing spouse for her assigned interest$22,000
GST/HST on the assignment consideration (13%)$2,860
Total closing cash required$70,860
Total debt serviceFigure
Payment at the qualifying rate (7.15%), 25 years$2,612/mo
Property tax$260/mo
Condo fees$340/mo
Car loan$220/mo
Total debt service39.0%

39.0% qualified comfortably on the solo purchaser's own income — the mortgage itself was routine. The GST/HST on the assignment was the number that had to be found and funded separately, in cash, before closing.

№ 04

The solution

A mortgage agent licensed under Ontario's Mortgage Brokerages, Lenders and Administrators Act treated the assignment's tax treatment as a question for the builder's and the couple's own lawyers to confirm, and structured the closing cash requirement only once that figure was settled.

First, confirmed with the couple's real estate lawyer that removing the departing spouse from the agreement was legally an assignment, not a simple amendment the builder could process without consequence.

Second, had the lawyer calculate the taxable consideration under Notice 323's rules, excluding the deposit-reimbursement portion but including the $22,000 paid for the interest itself, and confirmed the assignor was generally the party responsible for collecting and remitting the tax.

Third, sized the solo purchaser's closing funds to cover the additional down payment, the payment to the departing spouse, and the GST/HST together, so nothing was discovered for the first time at the lawyer's closing table.

Confirmation from the real estate lawyer that the transaction is an assignment under Notice 323
Calculation of the taxable consideration, separating any excluded deposit portion from the taxable balance
Confirmation of which party is responsible for collecting and remitting the GST/HST
Standard purchase documentation for the solo purchaser's own income, credit and down payment
№ 05

The outcome

The purchase closed at 5.15%, the $22,000 paid to the departing spouse and the $2,860 in GST/HST were both funded in cash at closing, and total debt service settled at 39.0%.

Because this file closed at 20% down, it is uninsured; the 39.0% figure sits comfortably inside CMHC's 44% TDS maximum regardless, for reference.

№ 06

What to take from this file

  • 01Removing one joint purchaser from a pre-construction agreement is usually an assignment, not a simple amendment. Confirm this with the builder and a real estate lawyer before assuming otherwise.
  • 02Since May 2022, every assignment sale of new housing is taxable — a marriage breakdown changes nothing about that. The old personal-use exemption no longer exists in any form.
  • 03A portion of the deposit reimbursed to the assignor can be excluded from the taxable consideration, but amounts paid for the interest itself generally are not. Have the lawyer separate the two before pricing the closing.
  • 04Build the GST/HST into the closing cash requirement, not the mortgage. It is a tax on the assignment, not a cost of the purchase itself, and most lenders will not finance it.

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.

Illustrative in this file — lender-specific, not rules:

  • 5.15% contract rate — rates move daily; not a quote.
  • the $22,000 assignment consideration — this couple's own negotiated figure; every assignment's consideration depends on the parties' own agreement.
  • the TDS figure — this file closed at 20% down and is uninsured, so there is no CMHC ratio ceiling; shown for reference only.

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.

First published 11 August 2026Rules last verified 11 August 2026Next scheduled review 11 February 2027

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.

Treadstone fulfillment

Files like this are daily work for our desk.

Document collection, ratio math under multiple treatments, lender placement notes, and submission-ready packaging — for Canadian mortgage brokers who would rather be in front of clients.