Assignment sales: what is actually left after the builder, the CRA and everyone else
Selling your pre-construction agreement before closing looks like easy money. Here is every deduction between the headline uplift and the cheque.
2026-08-28 · eXp Realty, Brokerage
An assignment is the sale of your agreement to buy — not the home, which does not exist yet — to someone who will close in your place. Prices rose, you sell for $110,000 more than you agreed to pay, everyone is happy. Then the deductions start.
The list
Builder consent fee. Most agreements require consent and charge for it: $5,000 is common, some charge more, some also require the assignee to buy upgrades.
Builder share of the uplift. Some agreements take a percentage of any profit. Read yours.
HST on the assignment. Since May 2022 every assignment of a new home is subject to HST on the assignment fee — the uplift. On $110,000 that is $14,300, and it is your obligation as the assignor.
Commission on the assignment sale price, plus HST on the commission.
Legal fees, on both the assignment and the eventual closing you are stepping away from.
Carrying costs to date: what your deposits could have earned, anything you paid the builder along the way.
Income tax. The CRA generally treats assignment profit as business income — fully taxable, not a capital gain with the 50% inclusion. The federal anti-flipping rule makes this explicit for properties held less than a year, and assignments are almost always caught. On $70,000 of net profit at a 43% marginal rate, that is $30,000 gone.
A worked example
Original price $850,000, assigned at $960,000, deposits paid $127,500:
| Gross uplift | $110,000 |
| HST on assignment | −$14,300 |
| Builder consent fee | −$5,000 |
| Commission 2.5% + HST | −$27,120 |
| Legal | −$2,500 |
| Carrying costs | −$3,000 |
| Net before income tax | $58,080 |
| Income tax at 43% | −$24,974 |
| After tax | $33,106 |
That is a real return on $127,500 of deposits, but it is 30% of the headline. The assignment tool does this for your numbers.
Two things to check before you list
Your agreement may prohibit advertising the assignment on MLS or anywhere public. And the assignee has to qualify with the builder — if they fall through, you are still closing.
Estimates only, for information. Not mortgage, tax or legal advice. Rates, rules and rebates change; confirm every figure with your lender, lawyer and the CRA before you rely on it.
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