How to Get a GST/HST Number in Canada: Registering for a GST/HST Account

As a Canadian business owner, staying compliant with tax regulations is crucial to keep operations running smoothly and avoid penalties. If your business has earned more than CAD $30,000 in taxable revenue across any four consecutive calendar quarters, the Canada Revenue Agency (CRA) requires you to register for a GST/HST number.

Navigating the registration process can seem daunting, but it’s straightforward with the right guidance. Registering online through the CRA's Business Registration Online portal is the fastest, easiest way to get a BN and a GST/HST account. 

This guide walks through the six steps to register, what to do if you've already crossed the threshold without registering, and what operational changes to make once the number is active. By the end, you'll have a clear understanding of how to register for a GST/HST number and be well-equipped to handle this important part of your business's financial management.

Key takeaways

• Know when you need to register. Most Canadian businesses must register for a GST/HST account once their taxable revenue exceeds $30,000 in a single calendar quarter or over four consecutive calendar quarters. Registration is optional for eligible small suppliers below this threshold.
• Register through the CRA. Use the CRA’s Business Registration Online portal to register for a Business Number (BN) and GST/HST account. Have your business details, expected revenue and fiscal year-end ready to make the process easier.
• Stay on top of your tax obligations. Once registered, charge GST/HST on taxable sales, file returns and remit the tax collected by your deadlines. You may also be able to claim input tax credits (ITCs) for GST/HST paid on eligible business expenses.

What is a GST/HST number?

A GST/HST number is a CRA account identifier that allows Canadian businesses to collect and remit the Goods and Services Tax (GST) or Harmonized Sales Tax (HST). Most businesses must register once their taxable revenue exceeds the CRA’s $30,000 small-supplier threshold.

Your GST/HST number consists of your nine-digit Business Number (BN) followed by the program identifier RT and a four-digit account reference. You use it to charge GST/HST on taxable sales, claim input tax credits (ITCs) on eligible business purchases, and file tax returns.

Your Business Number stays the same across CRA program accounts, including GST/HST, payroll and corporate income tax. Each account has its own identifier to distinguish it from the others.

How do I know if I need a GST or HST number, or both? 

The type of sales tax you charge depends on where your business operates and where your customers are located. GST applies federally, while HST combines the federal GST with a provincial portion in participating provinces.

If your business is registered for GST/HST, the tax you charge generally depends on the place of supply rules, which determine where a sale is considered to take place. For example, businesses selling to customers in Ontario generally charge 13% HST, while businesses selling to customers in Alberta generally charge 5% GST.

You don't need separate GST and HST numbers. Both taxes fall under the same CRA GST/HST program account. If you're required to register, the CRA will issue one GST/HST account number that you use to collect and remit the applicable tax.

Who Needs to Register for GST/HST? 

Whether you need to register depends on your business's revenue. You must register once your taxable revenue exceeds CAD $30,000 across four consecutive calendar quarters, or in a single calendar quarter.

These are two distinct triggers:

• Cross $30,000 within a single calendar quarter: You must start charging GST/HST on the sale that pushes you over the threshold. Your effective registration date is no later than that sale, and you have 29 days from that date to complete your registration.
• Cross $30,000 cumulatively across four consecutive calendar quarters: You stop being a small supplier at the end of the month following the quarter in which you exceed the threshold. You must start charging GST/HST on your first taxable sale after that date and register within 29 days of your effective registration date.

Below that threshold, you're considered a small supplier and registration is optional. Even though it's optional, many small suppliers register anyway to start claiming input tax credits.

Waiting has a real cost, not just an administrative one. If you're required to register and don't, you may owe the CRA GST/HST dating back to when you were required to start collecting it. The 29-day rule gives you time to complete the registration process, not extra time to start charging tax. If you're required to collect GST/HST, you must start on your effective date of registration, even if your registration application isn't complete.

Differences between sole proprietors and corporations

The GST/HST registration process is generally similar for sole proprietorships and corporations, but the business structure affects how you register and which details you'll need to provide.

• Sole proprietorships: If you're a sole proprietor, you can register for a GST/HST account under your existing Business Number (BN), if you have one. If you don't have a BN, you can obtain one during registration. As a sole proprietor, you're personally responsible for collecting and remitting GST/HST on your business's taxable sales.
• Corporations: If your business is incorporated, you'll generally use the corporation's Business Number to register for a GST/HST account. The corporation is a separate legal entity, so its GST/HST obligations are distinct from your personal tax obligations.

Both sole proprietorships and corporations must follow the same $30,000 small-supplier threshold when determining whether registration is required. If you operate multiple businesses as a sole proprietor, their taxable revenues generally count together toward this threshold. The CRA generally assesses a corporation's revenue separately from your personal sole proprietorship revenue.

Regardless of your business structure, you can register voluntarily before reaching the threshold if you meet the CRA's requirements. This may allow you to claim input tax credits (ITCs) on eligible business expenses, but it also means you'll need to charge GST/HST on taxable sales and meet the associated filing and remittance requirements.

How to register for a GST/HST number

Registration can feel overwhelming, especially as another to-do as your business grows. Follow these steps for a smooth registration. 

Step 1: Determine your eligibility and effective date

First confirm you've crossed the $30,000 threshold (or want to register voluntarily as a small supplier), and identify the date registration became mandatory. That date determines whether you owe backdated GST/HST. If you are below $30,000 and don’t want to register, you can stop here.

Step 2: Gather your business information

You'll need your Business Number (BN). If you don't already have one, you can register for one online through the CRA's Business Registration Online portal. The BN is essential for setting up your GST/HST account. You'll also need your fiscal year-end, expected annual revenue, business activity classification, and the business's legal and operating names.

Step 3: Choose your reporting period

The CRA assigns your reporting period based on your annual taxable revenue. Most businesses with $1.5 million or less in annual taxable supplies file annually, while higher-revenue businesses generally file quarterly or monthly. You can also choose to file more frequently to claim input tax credits (ITCs) sooner. See the CRA’s reporting period guidelines for more information. 

Step 4: Register through Business Registration Online

Register online through the CRA's Business Registration Online portal, by phone, or by mail. The CRA says registering online is the fastest and easiest way to get a business number and a GST/HST account. The CRA does not publish a specific turnaround time, so don't promise the reader one.

Quebec’s exception

If your business is located in Quebec, you'll generally register for GST/HST through Revenu Québec rather than the CRA. Revenu Québec administers GST and QST (Quebec Sales Tax) for most businesses operating in the province. You can register for both accounts through Revenu Québec and will need to follow its filing and remittance requirements. Visit Revenu Québec for registration instructions.

Step 5: Confirm your account and start charging GST/HST

Once registered, you'll receive your 9-digit business number with an RT program account identifier (for example, 123456789RT0001). Start charging GST/HST on taxable supplies from your effective registration date, and note that date if it's backdated.

Step 6: Set up your filing and remittance schedule

Confirm your assigned filing frequency and first return due date. Late filing carries penalties even if no tax is owed for the period, so calendar the due date as soon as your account is confirmed.

Special registration cases

Not every business follows the same registration path. If your business has unique circumstances, confirm which rules apply before submitting your application.

Registering in Quebec

Businesses operating in Quebec generally register for GST/HST and QST through Revenu Québec rather than the CRA. See the Quebec-specific guidance in Step 4 above for details.

Registering before you reach $30,000

You can register voluntarily if your business is still below the small-supplier threshold. This can be useful if you're making significant taxable purchases and want to recover the GST/HST paid on eligible expenses through input tax credits (ITCs). Just remember that registration also means you must charge GST/HST on applicable sales, file returns and remit any tax owing.

Registering after you've crossed the threshold

If you've already exceeded the $30,000 threshold but haven't registered, don't put off addressing it. Confirm when you were required to start charging GST/HST, gather your sales and expense records, and register as soon as possible. If you're unsure of your effective registration date or how to report past sales, contact the CRA for guidance. You may owe GST/HST on sales dating back to the date you were required to collect it.

Mistakes to avoid for GST/HST registration in Canada

Registering is only the first step. How you collect, track and remit GST/HST matters just as much. Here are five common mistakes to avoid.

Not collecting GST/HST when you're required to

Once you're required to register, you must start charging GST/HST from your effective registration date, even if you haven't completed the registration process. The 29-day registration window isn't extra time to delay collecting tax. If you've already crossed the threshold without registering, confirm when your obligation began and address any unreported tax as soon as possible to avoid potential interest and penalties.

Charging the wrong tax rate for a customer's province

The correct rate depends on the place-of-supply rules, which vary by the type of product or service you sell. For services, the customer's address is generally an important factor, even if you perform the work elsewhere. For example, an online business in PEI serving a customer in Ontario may need to charge Ontario's 13% HST rather than PEI's 15%. Check the CRA's place-of-supply guidelines to confirm the applicable rate.

Missing filing and remittance deadlines

Your reporting period determines when you must file returns and pay any balance owing. Confirm your filing frequency and first due date when you register, then set calendar reminders for both. Missing a deadline can result in penalties and interest. If you can't pay in full, contact the CRA to discuss your options.

Sending your payment to the wrong CRA account

GST/HST payments must go to your GST/HST program account, not your corporate income tax or payroll account. When paying through online banking, select the correct CRA payee and follow the payment instructions. Keep your confirmation and check your CRA account to ensure the payment was applied correctly.

Losing track of input tax credits

You can claim input tax credits (ITCs) on eligible business purchases, but you need records to support them. Keep invoices and receipts showing the GST/HST paid, verify supplier registration when required, and track tax on eligible expenses. Good record-keeping helps you recover what you're entitled to without claiming unsupported amounts.

Treating collected GST/HST as operating cash

GST/HST collected from customers isn't revenue you can freely spend. Consider transferring it into a separate business account so the funds are available when your remittance is due. Reviewing the balance regularly can help prevent a cash shortfall at filing time.

What changes once you're registered

Three main things change the day your GST/HST account becomes active.

1. You can start claiming input tax credits, and the math is worth doing before you assume it's marginal

An ITC recovers the GST/HST you paid on business purchases. On CAD $5,000 of office rent taxed at 13% HST, that's CAD $650 recoverable, every month, on that one expense alone. Claiming ITCs on employee expenses (travel, client meals, mileage) requires the same GST/HST-aware record-keeping the CRA expects for any input tax credit.

Float's expense reimbursement policy template and travel expense policy template are both built around claiming input tax credits on employee expenses and a Canadian travel expense policy that accounts for GST/HST recovery, respectively.