Pay a supplier whose Goods and Services Tax/Harmonized Sales Tax (GST/HST) number is fake, and the Canada Revenue Agency (CRA) can deny your input tax credits on audit. A wrong or borrowed number quietly turns a routine invoice into a rejected claim.
The good news: verification is free, takes minutes, and runs on two official government tools. Use the CRA GST/HST Registry to confirm a GST/HST account, and the government’s Canadian Business Registry to confirm corporate registration. There is no separate tool that validates a bare Business Number (BN) on its own.
Can You Verify a Canadian BN Online?
Not directly. No public tool validates a bare 9-digit BN by itself. You verify what the BN is attached to: its GST/HST account, through the CRA GST/HST Registry, or its corporate registration, through the Multi-jurisdictional Registry Access Service (MRAS) Canadian Business Registry run by Innovation, Science and Economic Development Canada (ISED). Each tool answers a different question.
| Feature | CRA GST/HST Registry | MRAS Canadian Business Registry (ISED) |
|---|---|---|
| What it confirms | GST/HST (RT) account registration on a given date | Corporate registration/incorporation status across jurisdictions |
| Inputs required | First 9 digits of the account number, exact business name, transaction date | Business name or BN |
| Output | Yes/no match as of the date entered | Registration record and status (e.g., Active) |
| Cost | Free, no login (CRA) | Free, no account (ISED) |
| Historical status | No history; point-in-time only (CRA) | No status-change history |
Sources: CRA, “Confirming a GST/HST account number”; ISED, Canadian Business Registry (MRAS).
Neither tool shows historical status changes. For account history or deregistration reasons, you must contact the CRA directly at the Business Enquiries line, 1-800-959-5525, per the CRA.
What Is a Canadian Business Number (BN)?
A Business Number (BN) is a unique 9-digit identifier issued by the Canada Revenue Agency (CRA) that acts as your common client identifier across federal programs, per the CRA business number pages. The CRA introduced the BN in 1994 to consolidate what used to be separate account numbers for corporate income tax, GST/HST, and payroll, per the CRA.
The 9-digit root alone is the BN9. The full program account identifier, the BN9 plus a program code and reference number, is the BN15. One legal entity gets one BN9 and can hold several program accounts under it.
What Does the BN Number Format Look Like?
A full BN15 is the 9-digit BN root, a 2-letter program identifier, and a 4-digit reference number, for example 123456789RT0001 for a GST/HST account, per the CRA. The Canada Border Services Agency (CBSA) uses the same structure: BN9 is the entity, BN15 is a specific program account.
The 2-letter code tells the CRA which program the account belongs to. Current identifiers include the following.
| Program code | Program | Status |
|---|---|---|
| RT | GST/HST | Active (CRA) |
| RP | Payroll deductions | Active (CRA) |
| RC | Corporation income tax | Active (CRA) |
| RM | Import/export | Now administered by CBSA, not CRA, since October 21, 2024 (CRA) |
| RR | Registered charities | Active (CRA) |
| RZ | Information returns | Active (CRA) |
| RD | Excise duty | Active (CRA) |
| RE | Excise tax and special levies | Active (CRA) |
| RN | Insurance premium tax | Active (CRA) |
| RG | Air travellers security charge | Active (CRA) |
| RU / LT / PT | Underused housing tax / luxury tax / global minimum tax | Active, newer codes (CRA) |
| DT | Digital services tax | Registration unavailable; tax slated to be rescinded (CRA) |
Source: CRA, “Which program accounts you need”.
Common format errors cause failed searches: dropping the 2-letter program code, using the wrong 4-digit suffix, adding spaces, or mistyping the 9-digit root. The CRA processes filings against the full BN15, so the whole string has to be correct.
When Does a Business Need a BN?
The BN is the foundation of federal tax compliance: you cannot register for GST/HST (the RT account), payroll deductions (the RP account), or corporate income tax (the RC account) without one, per the CRA. It links every program account to a single legal entity.
Common registration triggers include incorporating (many provinces auto-issue a BN), hiring employees, and importing or exporting goods (the RM account, now handled through the CBSA CARM Client Portal). GST/HST registration becomes mandatory once your worldwide taxable revenue exceeds the $30,000 small-supplier threshold over four consecutive calendar quarters, or in a single quarter, per the CRA. The threshold is $50,000 for public service bodies and $250,000 gross revenue for charities and public institutions under the Excise Tax Act. Once you cross it, you must register within 29 days of the sale that pushed you over, per the CRA.
Why Verify a Supplier’s BN Before Payment?
The strongest reason is input tax credit (ITC) protection: if a supplier charges GST/HST but is not actually registered, the CRA can deny your ITC claim on audit. Verification also prevents fraud, since a bad actor can invent or borrow a GST number to collect tax it never remits. And it is a standard Know Your Business (KYB) step in vendor onboarding and accounts payable (AP) workflows.
There is a holder’s side too. Your own valid BN is a trust signal. Clients, banks, lenders, and government contract programs routinely check it before doing business with you.
The legal weight varies by who you are. Under the Proceeds of Crime (Money Laundering) and Terrorist Financing Act (PCMLTFA), confirming business identity is a hard obligation for reporting entities such as financial institutions and money services businesses, overseen by the Financial Transactions and Reports Analysis Centre of Canada (FINTRAC). For everyone else, it is commercial risk management, not a statutory mandate.
How Do You Verify a GST/HST Number on the CRA Registry?
The CRA GST/HST Registry is a confirmation tool, not a discovery tool: you enter the first 9 digits of the account number, the exact business name, and a transaction date, and it confirms whether that account was registered on that date, per the CRA. You need the number and the name already; the registry matches them.
Follow these steps:
- Go to the CRA GST/HST Registry page on canada.ca.
- Enter the first 9 digits of the GST/HST account number. A malformed entry like “RT236578965” fails because the RT code belongs after the 9-digit root, not in front of it.
- Enter the business or operating name exactly as registered.
- Enter the transaction date you want to confirm, usually the invoice date.
- Complete the CAPTCHA and search.
The registry returns a yes/no match for that date. Save the confirmation, with a timestamp, as part of your ITC records.
How Do You Look Up a Business on the Canadian Business Registry (MRAS)?
Search the MRAS Canadian Business Registry by business name or BN, then filter by status such as Active to see registration and incorporation details, per ISED. It connects federal and participating provincial registries (including BC, Alberta, Manitoba, Quebec, and Saskatchewan) in one free search with no account required.
This is the discovery tool the CRA registry is not. Use MRAS when you have a company name but no number. Use the CRA registry when you have a number and need to confirm its GST/HST status. The two answer different questions and complement each other.
How Does BN Verification Protect Your GST/HST Input Tax Credits?
If a supplier charges GST/HST but is not registered, the CRA can deny your input tax credit (ITC) claim on audit. The CRA’s documentary requirements also dictate exactly what an invoice must show before an ITC is valid, and the required detail scales with the invoice amount.
| Invoice amount | Required supporting information | Source |
|---|---|---|
| Under $100 | Supplier name, invoice date, total amount | CRA (ITC Information Regulations) |
| $100 to $499.99 | Adds supplier’s GST/HST registration number and tax amount or rate | CRA |
| $500 or more | Adds recipient’s name and payment terms | CRA |
These thresholds rose to $100 and $500 (from $30 and $150) effective April 20, 2021, per the CRA’s documentary requirements guidance and the Input Tax Credit Information Regulations.
Keep the documents. The Canada Revenue Agency generally requires businesses to retain supporting records for six years, and you need them to defend ITC claims if the CRA reviews your file.
What If a BN Check Returns Invalid or Inactive?
A mismatch is usually a data-entry problem, not proof of fraud. Most failed searches trace back to a wrong number format, a name that does not match the registered name, or the wrong date. Work through the likely cause before assuming the supplier is illegitimate.
| Result | Likely cause | Fix |
|---|---|---|
| No match found | Typo, extra characters, or wrong structure | Re-enter the first 9 digits carefully, no spaces or letters |
| Not registered for GST/HST | Business exists but has no RT account | Confirm whether GST/HST registration applies; check MRAS |
| Inactive on the effective date | Registered after, or cancelled before, that date | Try the invoice date; contact the supplier |
| CAPTCHA validation failed | CAPTCHA entered incorrectly | Refresh and re-enter |
| Too many searches | Repeated rapid checks | Wait a few minutes and retry |
The registry shows point-in-time status only, with no history of status changes or deregistration reasons, per the CRA. For status history, call CRA Business Enquiries at 1-800-959-5525.
How Can Foreign Companies Verify a Canadian Tax ID?
Yes, foreign companies can run the same checks. Both official tools, the CRA GST/HST Registry and the MRAS Canadian Business Registry, are free, public, and require no Canadian presence or CRA login. Non-resident businesses that register for GST/HST appear in the registry the same way domestic ones do, so an overseas buyer or platform can confirm a Canadian supplier’s tax registration before paying.
How Do Finance Teams Automate BN Validation at Scale?
Manual, one-at-a-time registry checks do not scale across a large vendor master. The CRA registry has a CAPTCHA and no batch mode, so procurement and AP teams instead validate at onboarding and before large payments, typically through bulk upload or an API that flags mismatches and keeps an audit trail.
Commenda’s global indirect tax platform handles this by validating supplier tax registrations and keeping GST/HST compliance tracked across jurisdictions, with 100+ ERP, API, and custom integrations to fit into your existing finance stack. That turns a repetitive manual check into a step your systems run automatically.
How Commenda Helps With Canadian BN Verification
Verifying a Canadian BN is free and fast for one supplier, but it does not scale across a full vendor base. Commenda’s global indirect tax platform validates supplier tax registrations and keeps your GST/HST compliance handled across jurisdictions, so a check you used to run by hand becomes a step your systems own. Pair it with Commenda’s global tax ID verification tool for cross-border onboarding and its compliance calendar to stay ahead of filing deadlines. For the underlying rules, see our guides on sales tax in Canada and GST/HST registration for foreign companies.
Book a demo to see Commenda automate supplier tax ID checks across your entire vendor base, so your input tax credits hold up on audit and your team can close the laptop at 6.
