GST/HST when you build for a living
Most GST/HST guidance is written for shops that sell things. Construction is different in three specific ways: your rate follows the building rather than your office, your holdback is not taxable when you invoice it, and the paperwork your subcontractors give you decides whether you can claim the tax back. Those three are what this page covers.
The rules, with sources
Every line below links to the authority it came from and the date we last read it.
| The rates | 5% GST where the supply is made in a non-participating province. 13% HST in Ontario. 14% HST in Nova Scotia on or after April 1, 2025. 15% HST in any other participating province — New Brunswick, Newfoundland and Labrador, and Prince Edward Island. |
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checked 2026-09-08
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| Which province's rate applies | For services in relation to real property, the place of supply is where the property is. If the property is located primarily (more than 50%) in participating provinces, the place of supply is the participating province holding the largest proportion of it — otherwise it is a non-participating province. |
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checked 2026-09-08
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| When you must register | You stop being a small supplier once worldwide taxable supplies from you and your associates exceed $30,000 in a single calendar quarter or over the last four consecutive calendar quarters. You must register within 29 days of your effective date of registration. |
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checked 2026-09-08
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| Tax on holdback | Where a written construction agreement or the law requires an amount to be held back, tax on that amount is payable on the earlier of the day the holdback is paid out and the day the holdback period expires. |
ETA s. 168(7) ↗
checked 2026-09-08
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| What a sub's invoice must show | Under $100: the supplier's name, the date, and the total. $100 to $499.99: also the supplier's GST/HST registration number and the tax amount or a statement that tax is included. $500 or more: also your name, the terms of payment, and a description of the supply. Thresholds rose from $30 and $150 on April 20, 2021. |
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checked 2026-09-08
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Your rate follows the building, not your truck
This is the one that costs money. A Quebec company painting a warehouse in Ontario charges 13% Ontario HST, because the property the service relates to is in Ontario. Where your office is, where the crew sleeps, and where you sent the invoice from do not enter into it.
Cross a provincial line and the rate changes with it. If you work in more than one province, the rate is a property of the job, not a setting on your invoice template — which is exactly how contractors end up under-collecting on an out-of-province job and paying the difference themselves years later.
Holdback is the exception everyone bills wrong
The normal rule is that tax becomes payable when the invoice is issued. Holdback is carved out: for a holdback required by a written construction agreement or by legislation, no tax is payable on the held-back amount until the earlier of the day it is paid out and the day the holdback period expires.
In practice that means a progress claim should charge tax on the amount actually payable now, and the tax on the 10% follows later when the holdback is released. Charging it up front is the common error — it does not make you non-compliant, but it means you have remitted tax on money you have not received, sometimes for a year. Our Ontario holdback guide, linked below, covers when that release actually happens.
No registration number on the invoice, no input tax credit
Once a purchase is $100 or more, the supplier's GST/HST registration number has to be on the paperwork before you can claim the credit. At $500 or more you also need your own name, a description of the supply, and the terms of payment.
Subcontractor invoices routinely fail this — a number scrawled on a work order is not the same as a registration number on an invoice. The time to fix it is when the invoice arrives, not when the CRA asks you to prove a year of credits. It is worth checking that the number is real: the CRA has a free registry for confirming a GST/HST account number.
Questions people actually ask
What GST/HST rate do I charge on a job in another province?
The rate of the province where the property is. For services in relation to real property, the place of supply is where the real property is located — so a contractor based in one province charges the rate of the province the building is in.
Do I charge GST/HST on holdback?
Not when you invoice it. For a holdback required by a written construction agreement or by law, tax on the held-back amount is payable on the earlier of the day the holdback is paid out and the day the holdback period expires.
When do I have to register for GST/HST as a contractor?
Once your worldwide taxable supplies exceed $30,000 in a single calendar quarter or over the last four consecutive calendar quarters. You then have 29 days to register.
What is the GST/HST rate in Nova Scotia?
14%. Nova Scotia reduced the provincial portion of the HST effective April 1, 2025, down from 15%.
What does a subcontractor's invoice need for me to claim the ITC?
At $100 or more it needs the supplier's GST/HST registration number and the tax amount. At $500 or more it also needs your name, a description of the supply, and the terms of payment.
Is the ITC threshold still $30 and $150?
No. Those thresholds were raised to $100 and $500 effective April 20, 2021.
GoBuild applies tax per job rather than per company, so a job in another province carries that province's rate, and it keeps holdback as its own line so the tax on it is not billed before it is payable. It does not file your return — your accountant still does that.
More guides
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The 10% basic holdback, the 28-day and 7-day prompt payment deadlines, and the 60-day lien window — quoted fro…
There is no general contractor's licence in Ontario — but building or selling a new home needs an HCRA licence…
This is a plain-English summary written for contractors, not legal or tax advice, and it is not a substitute for reading the source or talking to your accountant or lawyer. Rules change; each line above carries the date we last checked it. If you find something out of date, tell us and we will fix it.