Business Number vs Corporation Number: What's the Difference and Why It Matters
This registration is free and can be completed online through the CRA Business Registration Online portal. Understanding Ontario incorporation fees is equally important — the 300 Ontario government fee covers your OCN registration, but CRA Business Number registration is a completely separate and free process completed after incorporation.
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When you incorporate a company in Ontario, you receive two separate identification numbers — a Corporation Number from ServiceOntario and a Business Number from the Canada Revenue Agency. Most new business owners confuse these or assume they are the same. They are not, and using the wrong one in the wrong context can cause significant administrative problems.
What Is an Ontario Corporation Number?
Your Ontario Corporation Number (OCN) is assigned by ServiceOntario at the moment your incorporation is approved. It is a unique identifier used exclusively for provincial government purposes — filing annual returns, updating corporate records, and communicating with ServiceOntario.
When you register a company in Ontario, your OCN is generated automatically — you do not need to apply for it separately. It appears on your Certificate of Incorporation and should not be provided to the CRA for tax purposes.
What Is a Business Number?
A Business Number (BN) is a 9-digit identifier assigned by the Canada Revenue Agency. It is your corporation's primary identifier for all federal tax purposes — corporate income tax, HST/GST, payroll deductions, and import/export accounts.
Unlike the OCN, a Business Number is not automatic. After incorporating you must register separately with the CRA to receive it. This registration is free and can be completed online through the CRA Business Registration Online portal.
Understanding Ontario incorporation fees is equally important — the $300 Ontario government fee covers your OCN registration, but CRA Business Number registration is a completely separate and free process completed after incorporation.
For a detailed breakdown of the differences, when to use each number, and how to register for both, read this complete guide: Business Number vs Corporation Number Canada — bizincs.com/business-number-vs-corporation-number-canada/
Why This Distinction Matters for Ontario Business Owners
Confusing these two numbers causes real problems. Providing your OCN to the CRA instead of your BN delays tax filings and account registrations. Providing your BN to ServiceOntario for annual return purposes causes processing errors.
Once you understand that these are two separate systems — provincial and federal — managing your corporation's compliance becomes significantly simpler.
Conclusion:
Every Ontario corporation operates with two separate identification numbers — one provincial, one federal — and each serves a distinct purpose. When calculating the cost to incorporate in Ontario, remember that while the provincial incorporation fee covers your Corporation Number, your Business Number registration with the CRA is an additional step — though it costs nothing to obtain. Get both numbers in hand before you start operating and your compliance obligations become significantly simpler.
