If you build, renovate, or flip houses — even occasionally, even alongside a regular job — you could owe GST/HST on the sale without realizing it. A recent Tax Court of Canada decision is a good reminder of how easily an individual can cross from “homeowner” into “builder” in the eyes of the CRA, and what that means for your tax bill.
The Case That Prompted This
In a February 2026 ruling, the Tax Court considered a couple who had repeatedly built and sold houses. Over an 11-year period, they purchased seven properties and sold five, including several built from bare land. After completing and moving into their most recent home in British Columbia, the CRA reassessed them for over $22,000 in GST for the reporting period when they first occupied it.
The couple argued two things: first, that they weren’t “builders” under the legislation and therefore didn’t owe GST at all; and second, that even if they were considered builders, the house had been built primarily as their family residence, which should qualify them for a personal-use exception. The court rejected both arguments — and the reasoning is instructive for anyone in a similar position.
Who Counts as a “Builder”?
Under GST/HST rules, you don’t need to be a professional developer to be treated as a builder. The CRA and the courts look at the pattern of your activity, including:
- Frequency — how many times you’ve built or substantially renovated and sold property
- Ownership and occupancy period — how long you actually lived in each property before selling
- Experience and intent — whether your history shows familiarity with building and selling for profit, rather than simply living somewhere long-term
In the case above, the court found the couple were builders precisely because of how often they’d repeated the pattern, how short their occupancy periods tended to be, and their clear experience with construction and resale.
What Being a “Builder” Means for GST/HST
If you’re considered a builder, you may be required to remit GST on the “self-supply” of the property — essentially, GST calculated as though you’d sold the property to yourself at fair market value the moment you began using it (for example, when you first moved in). This applies whether or not you go on to actually sell the property to someone else afterward.
The Personal-Use Exception — and Its Limits
There is a narrow exception for individual builders: if a property is used primarily as a residence by you or a relative, and it hasn’t been used primarily for any other purpose between substantial completion and that residential use, GST on the self-supply may not apply.
But this exception is harder to rely on than it sounds. In the case above, the court found the couple’s occupancy lacked the “enduring quality” of a genuine family residence. Their stay was brief, and the court viewed it as incidental to a broader, repeated pattern of building and selling for profit — not a case where resale was a secondary afterthought and the home was truly meant to be lived in long-term.
The key distinction courts draw is:
- Genuine residence, later sold → personal-use exception more likely to apply
- Property functioning as inventory, briefly occupied → exception unlikely to apply, even if you did live there for a time
Practical Takeaways
If you’re building or substantially renovating homes with any regularity — even as a side activity — it’s worth asking:
- How does this fit your overall pattern? One house, built and lived in for years before an unplanned sale, looks very different to the CRA than a fifth flip in a decade.
- Can you document your intent? Real evidence of intending to live somewhere long-term (and a plausible, well-supported reason for an unexpected sale) matters more than a stated intention after the fact.
- Talk to a tax professional before you build, not after you sell. GST/HST self-supply rules are triggered at the point of substantial completion and first use — by the time you’re selling, the obligation may have already crystallized.
Bottom Line
Buying and selling houses as an individual doesn’t automatically make you a “builder” for GST/HST purposes — but a repeated pattern, short ownership periods, and evident construction experience can tip the scales quickly. If resale is part of your plan (or becomes part of your pattern), it’s worth understanding your GST/HST exposure before, not after, the CRA does.
General information only; not legal or tax advice. Consult a qualified tax professional about your specific situation.
