The Old Law vs. The Bill C-4 Overhaul
TL;DR: The Bill C-4 GST rebate for new homes now covers 100% up to $1,000,000, saving first-time buyers up to $45,000 compared to the outdated limits.
The previous framework, drafted in 1991 when the average Ontario home cost under $200,000, provided a 100% GST rebate only on homes priced below $350,000, phasing out entirely at $450,000. In 2026, there are effectively zero new homes available in Ontario's major markets below that threshold — meaning the pre-C-4 rebate had become a dead letter for virtually every buyer in the province.
Bill C-4 resets the entire equation. The full 100% GST rebate has been extended to qualifying new homes up to $1,000,000, with a partial rebate phasing out at $1,500,000. On a $900,000 new build, that translates to approximately $45,000 in federal tax relief that simply did not exist before May 27, 2025.
The Effective Date Trap: Why Your Closing Date Is Critical
TL;DR: The enhanced GST/HST rebate only applies if your final closing date is after May 26, 2025.
The CRA has confirmed that the enhanced rebate applies to eligible transactions where final closing occurs after May 26, 2025. Buyers who took possession on interim occupancy before this date but whose final closing date falls after May 27, 2025 may still qualify — but this requires a formal review of your specific transaction with a qualified real estate lawyer or tax professional. Do not assume either way without professional confirmation.
If your builder is pushing for an early final closing that would move your transaction before this threshold, you have a material financial interest in understanding your Tarion-protected rights to delay. An early closing could cost you tens of thousands in lost rebate entitlement.
What Builders Are Doing With the Rebate
TL;DR: Builders often assign the rebate to themselves, so you must confirm if the advertised price is inclusive of the new C-4 rebate.
Most builder contracts for new homes price the HST rebate as "assigned to the builder" — meaning the advertised price is already net of the rebate amount, and the builder receives the rebate directly from the CRA. Under C-4, the magnitude of this assigned rebate has increased dramatically, and some developers are restructuring their pricing models as a result. First-time buyers should ask their sales rep explicitly: "Is the purchase price inclusive or exclusive of the HST rebate?" The answer changes your true net cost by up to $45,000.