GST for Contractors in Canada: What Every Contractor Should Know Before Sending an Invoice?

You finish the job, send the invoice, and then face the question that can get a bit complicated: Do I need to charge GST on this? Getting the answer wrong can mean undercharging your customer, absorbing the tax yourself, or creating compliance issues with the CRA.

GST rules for contractors are easier to navigate when you know your taxable revenue, registration date, and what you’re billing for. Whether you’re charging for labour, materials, or both, understanding these rules helps you invoice correctly and avoid costly mistakes.

At LedgerNet, we work with contractors and trades businesses across Canada, helping them manage GST registration, invoicing, filings, and day-to-day accounting compliance.

Read on to learn when contractors need to register for GST, what to charge, and how to make sure every invoice is CRA-compliant.

When Contractors Are Legally Required to Charge GST

Whether you must charge GST depends on your revenue, and never your trade. The CRA does not care if you are incorporated or a sole proprietor.

One number decides this for every contractor in Canada. That number is 30,000 dollars in taxable revenue.

Once your revenue crosses that mark, you stop being a small supplier. This can happen within a single calendar quarter. It can also happen across four consecutive quarters.

Once you cross that line, charging GST is no longer optional. The CRA requires it by law from that point forward.

Stay under 30,000 dollars and registration is not mandatory. Many contractors still register anyway. It lets them claim back GST paid on their own tools and materials.

Are you asking do I need to charge GST as a contractor? Check your last four quarters of revenue. Your job title never decides this answer.

This is exactly where we help businesses in the trades track their numbers correctly.

GST Rules for Contractors Working in British Columbia

British Columbia charges GST only, at a flat 5 percent rate. BC does not use HST the way Ontario or Nova Scotia does.

Knowing when to charge GST in BC comes down to one date, your registration date. GST applies to every taxable invoice from that date onward.

Say you crossed 30,000 dollars in the middle of a project. That same invoice already needs GST charged on it. This applies even before your number physically arrives by mail.

Our services team helps BC contractors get this timing right from day one.

Why GST Applies to Labor Charges and Not Just Materials

Yes, GST applies to labor charges too, not only to materials. This single point trips up a lot of contractors early on.

Some assume tax only touches physical supplies, like lumber, parts, or fixtures. That assumption is incorrect under CRA rules.

You might bill labor and materials as one combined total. You might also split them into two separate invoice lines. Either method still means GST covers the full taxable amount.

Contractors searching do contractors charge tax on labor are often hoping for an exception. No such exception exists under current CRA rules.

When Does a Contractor Legally Need a GST Number?

Once you cross the 30,000 dollar threshold, a GST number becomes mandatory, not optional. You get 29 days from the date you exceed that threshold to register.

Without a valid number, you cannot legally charge GST on any invoice. That leaves you two bad options, absorbing the tax yourself or invoicing incorrectly.

Neither option protects a growing contracting business from CRA penalties later.

So the direct answer is this. Do I need a GST number as a contractor once revenue crosses that line? Yes, every single time, with no exceptions.

How to Register for a GST Number in Canada?

Registering is simpler than most contractors expect it to be. Canada offers three separate ways to complete this step.

You can register online through the CRA Business Registration Online portal. You can also call the CRA directly and register by phone.

A paper form sent by mail works too, for anyone who prefers it. This process to register for GST number Canada wide stays identical across every province.

For BC specifically, the same three registration options apply directly. Anyone asking how to get a GST number in BC follows this same CRA process.

The team at LedgerNet sees new contractors miss this registration step often.

Once registered, your GST number must appear on every single invoice. Your business name and the total tax charged need to sit alongside it.

Miss this detail, and your invoices no longer meet CRA requirements. This becomes a real problem the moment your business gets reviewed.

How LedgerNet Helps Contractors Stay GST Compliant

GST rules can cause the most invoicing mistakes.

GST often slips down the list amid WCB reporting, subcontractor payments, and project cash flow. Compliance gets deprioritized instantly.

Our team closes that exact gap for contractors across Canada every day. From registration decisions to ongoing filings, we manage the details for you.

If your GST situation needs a second set of eyes, book your slot today. Let's get your invoicing right from the very start.