The Business Number (BN) is a 9-digit identifier assigned by the Canada Revenue Agency (CRA) to every incorporated business in Canada. The BN is used as the root number for various CRA program accounts: HST (RT account), payroll (RP account), corporate income tax / T2 (RC account), import/export (RM account), and others. Every incorporated business needs a BN. Sole proprietorships and partnerships only need a BN if they register for one of the program accounts (typically HST when crossing the $30K revenue threshold, or payroll when hiring employees).
Effective November 3, 2025, the CRA stopped accepting BN, HST, and payroll registrations by phone. New tax account registrations must be completed through the CRA's Business Registration Online (BRO) portal, or through a Registry Consultant like Ontario Business Central. OBC handles the registration on your behalf without requiring you to set up BRO portal access yourself.
HST registration is mandatory once your business crosses $30,000 in worldwide taxable revenue across any 4 consecutive quarters. You have 29 days from the date you cross the threshold to register. Many small businesses choose to register voluntarily before hitting the threshold to claim Input Tax Credits (ITCs) on business expenses. Ontario HST is 13%.
The BN (Business Number) is the 9-digit federal CRA identifier for tax purposes. The BIN (Business Identification Number) is the 10-digit Ontario provincial identifier for OBR records. The Corporate Number is the legal incorporation number assigned at the time of incorporation. They serve different purposes — the BN is for taxes, the BIN is for the Ontario Business Registry, and the Corporate Number is the legal identifier of the corporation itself.
Yes. If you've lost your BN, OBC can retrieve it for Ontario, BC, and federal corporations. Provide the corporation name and (optionally) the BIN or Corporate Number, and we'll deliver the BN by email the same business day. This is also useful when buying a corporation, doing an accounting handover, or verifying a vendor's BN before issuing a T4A or T5018.
Not initially. A sole proprietorship or general partnership only needs a BN when registering for one of the CRA program accounts: HST (when crossing $30K), payroll (when hiring employees), import/export, or others. If you're operating below the HST threshold and have no employees, you may not need a BN at all, your personal SIN handles tax filing through your personal tax return.
Yes. Most new corporations register for BN + HST + Payroll in one transaction. OBC's New Tax Account Registration handles the bundle, we register all three program accounts (RT for HST, RP for payroll, plus the RC account for T2 corporate income tax which is auto-created with the BN) in a single same-day filing.
You'll need: the corporation's legal name and incorporation date, the registered office address, primary business activity (NAICS code or description), expected first-year revenue, fiscal year-end date, director and officer names, and contact information. For HST registration, you'll also need to confirm if you're voluntarily registering or registering because you've crossed the threshold. For payroll registration, you'll need to confirm the date you started or will start paying employees.
OBC's New Tax Account Registration is processed the same business day for orders received before our daily cut-off. The CRA typically issues the BN within hours of submission. The HST and payroll program accounts are activated at the same time as the BN. You'll receive the BN by email along with confirmation of the activated program accounts.
Closing a business doesn't automatically close your CRA program accounts. You must separately notify the CRA to close BN program accounts and file a final corporate tax return (T2). This is required after dissolving the corporation. We recommend closing CRA accounts in this order: close payroll (file final T4 and ROEs first), close HST, then file the final T2 for the corporate year. Speak with your accountant or our team about the right sequence.
