CRA Accounts
Business Number vs GST/HST Number: What's the Difference?
Business number vs GST number, explained: how the CRA BN works, why your GST/HST number is built on it, and when a Canadian sole proprietor needs each one.
Understanding the business number vs GST number distinction is one of the first things a new Canadian sole proprietor has to sort out. The short answer: a Business Number (BN) is your master CRA identifier, while a GST/HST number is simply your BN with a GST/HST program account attached. You are not juggling two unrelated numbers — the GST/HST account is an extension of the BN.
What Is a Business Number (BN)?
A Business Number is the nine-digit identifier the Canada Revenue Agency (CRA) uses to track a business across its tax programs. It is not a licence, and it does not replace business registration with a province or with Corporations Canada. Instead, it is an umbrella under which individual CRA program accounts sit. Each account is identified by a two-letter program code followed by a four-digit reference number:
- RT — GST/HST
- RP — payroll source deductions
- RC — corporate income tax
- RM — import/export
- RZ — registered charity
A sole proprietor may operate for years without a BN if no program account is required. When you do need one, the process is straightforward — our guide on how to get a Business Number in Canada walks through the online and phone options.
What Is a GST/HST Number?
Your GST/HST number is the BN plus the RT program account and its four-digit reference, which is why it looks like a BN with extra characters on the end. When a business registers only for GST/HST and has never had a BN, the CRA issues a BN at the same time, so the two arrive together.
Registration can be mandatory or voluntary. It typically becomes mandatory once your taxable revenues cross the small-supplier threshold, and voluntary registration is available in many cases before that point. Both paths are covered in our guide to how to register for GST/HST in Canada, and the revenue test itself is explained in the GST/HST registration threshold guide.
BN vs GST/HST Number at a Glance
| Feature | Business Number (BN) | GST/HST number |
|---|---|---|
| What it identifies | Your business with the CRA | One CRA program account (RT) |
| Typical format | Nine digits | BN, then RT and a four-digit reference |
| Issued by | CRA, or Revenu Québec in Quebec | CRA, or Revenu Québec in Quebec |
| Commonly needed for | Payroll, GST/HST, import/export, corporate tax | Charging and claiming GST/HST |
| Shown on invoices | Not usually required | Required once registered, subject to CRA invoicing rules |
Think of the BN as the filing cabinet and the GST/HST number as one labelled drawer inside it.
Do You Need Both as a Sole Proprietor?
Many sole proprietors need neither at the start. A BN appears only when you require at least one program account. Common triggers include:
- Registering for GST/HST because your revenues exceed the threshold, or because you choose to register voluntarily.
- Hiring employees and opening a payroll (RP) account to remit CPP, EI and income tax withholdings.
- Importing or exporting goods commercially and needing an RM account.
- Filing information slips such as a T4A for fees paid to contractors.
Registering for GST/HST automatically gives you a BN. The reverse is not true: a BN on its own does not make you a GST/HST registrant. If you are still deciding on structure, start with what a sole proprietorship is, then confirm whether registration applies to you.
Finding, Verifying and Managing Your Numbers
Your BN and GST/HST number appear on CRA notices, your registration confirmation, filed returns and slips. If you cannot find them, sign in to CRA My Business Account or call the CRA business enquiries line. Our CRA My Business Account guide covers setup. When a client or supplier asks you to confirm your number, your CRA documents and the BN lookup service are the reliable starting points for verification.
Using Your Numbers Correctly
Once you are a GST/HST registrant, you must show your GST/HST number on invoices above the amount CRA sets for its small-invoice exception, and you must charge and remit tax at the correct rate for your province. Confirm the current invoicing rule and rates on the CRA website rather than relying on a template. Keep your BN and program accounts current when you move or change your business name — our guide on updating your CRA business account explains how.
Common Mix-Ups to Avoid
Three mistakes show up repeatedly. First, quoting only the first nine digits when a client asks for your GST/HST number, when the RT and reference digits are part of what they need to verify you. Second, assuming a BN means you can charge GST/HST; registration is a separate step. Third, cancelling the entire BN when you only wanted to close the GST/HST account, which can disrupt payroll and other accounts. As of the current tax year, the CRA continues to distinguish clearly between the BN and its program accounts, and provincial business registries remain fully separate from both.
Frequently asked questions
Is a GST number the same as a business number?
No, but they are closely related. Your GST/HST number is your nine-digit Business Number combined with the RT program account and a four-digit reference number. If you register only for GST/HST and do not yet have a BN, the CRA issues one at the same time, so you end up with both. A BN alone, however, does not make you a GST/HST registrant.
Do I need a business number as a sole proprietor in Canada?
Only when you need a CRA program account. If you register for GST/HST, whether mandatorily or voluntarily, hire employees, or import goods commercially, you will get a BN as part of that process. Many sole proprietors operating under their own legal name, with no GST/HST registration and no employees, can run for years without one. Confirm your own situation with the CRA.
How do I find my GST/HST number?
Check your CRA registration confirmation, GST/HST returns, notices of assessment, or invoices you have issued. Signing in to CRA My Business Account shows your BN and each program account attached to it. If you cannot locate it, call the CRA business enquiries line. In Quebec, GST/HST is administered by Revenu Québec, so your number is found through your Revenu Québec file instead.
Can I have a GST/HST number without a business number?
Not in practice. The GST/HST account is a program account carried under a BN, so the CRA assigns a BN when you register, even if you hold no other CRA accounts. Because there is no separate standalone GST number in the CRA system, any invoice or document showing a GST/HST number is showing a BN with an RT extension. That is why the two are often confused.