Building a custom home on your own lot gives more control over layout, finishes, and long-term property value. However, HST can surprise homeowners during construction. Rebates may help reduce the final tax cost if you qualify. In 2026, first-time buyers may also qualify for additional GST/HST relief if their owner-built home meets CRA timing and completion requirements.
What “Building on Your Own Lot” Means for HST?
Building on your own lot means you already own the land where the home will be constructed. Instead of buying a completed home from a developer, you hire a custom builder or contractors to build directly on your property.
This setup commonly includes:
- Vacant land purchases
- Rural or estate properties
- Tear-down and rebuild projects
- Homes built on inherited family land
For HST purposes, the construction work is usually taxable. Labour, materials, subcontractor invoices, and builder services generally include HST. The land may be treated differently depending on how it was purchased.
How is HST Paid During Construction?
HST is usually paid gradually throughout construction rather than in one large payment at the end. Most builders use progress draws, where you pay at key stages of the project. Common stages include the deposit, foundation, framing, roofing, interior finishing, and completion.
Before signing, ask whether the quote is HST included or plus HST.
How does the HST Rebate Work for New Custom Homes in Ontario?
Ontario homeowners may recover part of HST through the New Housing Rebate when building or substantially renovating a primary residence using CRA Form GST191.
Federal GST Rebate
The federal rebate applies to the 5% federal GST portion of Ontario’s HST. CRA states that eligible individuals may recover 36% ( set by CRA) of the GST or federal part of the HST paid, up to a maximum rebate of $6,300.
Example:
- Construction cost: $300,000
- Federal GST portion: $300,000 × 5% = $15,000
- Federal rebate: $15,000 × 36% = $5,400
The standard federal rebate phases out as fair market value rises and is generally not available above the federal threshold.
Ontario Provincial Rebate
Ontario’s rebate applies to the 8% provincial portion of HST. CRA states that Ontario’s rebate can be available up to $24,000, even when the fair market value exceeds $450,000, if all other conditions are met.
Example:
- Construction cost: $300,000
- Ontario HST portion: $300,000 × 8% = $24,000
- Ontario rebate: $24,000 × 75% = $18,000
Combined, these rebates can recover a significant portion of HST paid during construction.
First-time Home Buyers’ (FTHB) GST/HST rebate
Eligible first-time home buyers may recover up to $50,000 of GST or federal HST on qualifying new, substantially renovated, or owner-built homes valued up to $1.5 million. Construction must begin after March 20, 2025, and before 2031, with substantial completion before 2036. The home must meet CRA ownership, residency, and completion requirements.
How to Qualify for the Rebate?
To qualify, homeowners generally must:
- Build or hire someone to build a home on land you own or lease
- Substantially renovate a home by removing or replacing at least 90% of the interior
- Add a major structural addition, such as a full second storey, that makes the home substantially new
- Convert a non-residential property into a home
- Purchase or substantially renovate a mobile or floating home
Homes built for resale or speculative investment purposes may not qualify.

How to Claim HST Rebate for New Custom Homes?
Rebate rules can change, especially with 2026 first-time buyer updates, homeowners should confirm eligibility before applying.
Most homeowners apply directly to the CRA after construction is substantially complete and ready for occupancy.
To claim:
- Collect invoices showing HST paid
- Gather construction contracts and payment records
- Determine the completed home’s fair market value
- Complete CRA Form GST191
- Have occupancy permits, land ownership records, and proof of primary residence ready, in case needed.
Many homeowners also work with their builder, accountant, or lawyer to complete the application properly.
For more information, visit Canada government’s GST/HST New Housing Rebate resource.
Luxury Custom Home Builder in Kingston
Work with a custom home builder in Kingston who takes the paperwork as seriously as the build. At YK Contractor, we provide clear itemized receipts, keep proper project records, and carry the insurance and warranty coverage needed for eligible work to support your Ontario HST rebate process.
A custom home involves many moving parts, from materials and trades to permits and final finishes. We keep everything organized, so you have a smoother build and the right documentation when it matters.
Book a free consultation to get started.


