The $30,000 HST decision
Every contractor eventually hits the HST question. Register too late and you owe tax you never collected. Register early and you get money back on everything you buy. Here's the line, and when it's worth crossing on purpose.
Updated for the 2026 tax year · figures verified 2026-08-02 · by Blue Crane Works
The line: $30,000 of gross revenue
You must register for HST once your gross revenue — what you invoiced, not what you kept — passes $30,000, measured either in one calendar quarter or across four consecutive quarters, per CRA's GST/HST registration rules. Under that, you're a small supplier and registration is your choice.
The expensive mistake: sailing past $30,000 without noticing, not charging HST, and then getting assessed for tax you never collected. Under CRA's GST/HST registration rules, the CRA can make you pay it regardless of whether you charged your customers — so it comes straight out of your margin. Watch your rolling four-quarter total.
When to register early on purpose
Registration isn't only an obligation — it's a tool. Once you're registered you claim Input Tax Credits: the HST you pay on materials, tools, fuel and supplies comes back to you. A contractor spending heavily on materials can be better off registering before hitting $30,000.
The deciding factor is usually your customers. Sell mostly to businesses? They reclaim the HST anyway, so charging it costs you nothing and the input credits are pure upside. Sell mostly to homeowners? Adding 13% makes your quote higher against unregistered competitors, so the timing matters more.
Once you're registered: the Quick Method
Registering isn't the end of the decision. Once you're charging HST, most Ontario trades can elect the Quick Method — remit a flat 8.8% of your HST-included sales instead of tracking every receipt, and keep the difference between that and the 13% you collected. For labour-heavy work with few taxable purchases, it's often found money. The Quick Method calculator shows your number and the break-even where it stops being worth it.
Where this fits
HST is separate from the income tax and CPP the calculator for your province estimates — it's a tax you collect and remit, not one on your income. But it's the other half of getting your contractor finances right, and the $30,000 line is the one nobody should cross by accident.
Common questions
When do I have to register for HST?
You must register once your gross revenue exceeds $30,000 in a single calendar quarter, or over four consecutive calendar quarters. Below that you're a 'small supplier' and registration is optional. The $30,000 is gross revenue — what you billed — not profit.
What happens if I go over $30,000 and didn't register?
You were required to register and charge HST from the point you crossed the threshold, and the CRA can assess the tax you should have collected — meaning it comes out of your own pocket if you never charged it. This is one of the more expensive contractor mistakes, and it's entirely avoidable by watching your rolling four-quarter total.
Should I register before I have to?
Often yes. Once you register you can claim Input Tax Credits — the HST you pay on tools, materials, fuel and other business purchases comes back to you. For a contractor buying a lot of materials, voluntary early registration can be net positive, especially if your customers are businesses that don't care about the added HST.
Does charging HST make me more expensive to customers?
To a homeowner, yes — your invoice is 13% higher. To a business customer, no real difference, because they claim the HST back themselves. So the 'should I register early' answer partly depends on who your customers are: mostly homeowners, or mostly other businesses.
Is GST/HST the same as income tax?
No — they're completely separate. HST is a sales tax you collect from customers and remit to the CRA; it isn't your money and isn't income tax. Income tax and CPP are charged on your profit. This calculator estimates income tax and CPP; HST is a separate obligation you manage alongside it.
How often do I remit HST?
It depends on your revenue. Smaller businesses typically file annually, larger ones quarterly or monthly. When you register, the CRA assigns a reporting period. Whatever the frequency, the HST you collected minus the input tax credits on your purchases is what you remit.
Keeping the paperwork straight is half of getting deductions right. Blue Crane captures receipts as you buy and builds an accountant-ready export, and its form maker builds the printable Ontario contractor forms. For compliance forms and rules, see Ontario Trade Registry.