What is the difference between a GST number, HST number, and QST/PST number — and which applies in which province?

Canada has a dual sales tax system. The federal GST (Goods and Services Tax, 5%) applies nationwide. In provinces that have harmonized with the federal system, GST and provincial sales tax are collected together as HST (Harmonized Sales Tax): Ontario (13%), Nova Scotia (15%), New Brunswick (15%), Newfoundland and Labrador (15%), Prince Edward Island (15%). The federal GST number (9 digits + RT account suffix) is used for both GST and HST. In non-harmonized provinces, separate provincial taxes apply: QST (Quebec Sales Tax, 9.975%) requires a separate QST registration; PST (Provincial Sales Tax) in BC, Saskatchewan, and Manitoba requires provincial registration; Alberta has no provincial sales tax. A supplier operating in Quebec must have both a federal GST number and a Quebec QST number.

My supplier is a non-Canadian digital services provider — do they need a regular GST registration or a Simplified GST account?

Non-resident digital service providers (streaming, software, app stores, SaaS) supplying to Canadian consumers may register under the Simplified GST/HST framework rather than the standard registration. Simplified registrations require less administrative burden but limit ITC (Input Tax Credit) claims. The CRA publishes a public list of businesses registered under the Simplified GST/HST rules for digital services at canada.ca/en/revenue-agency/services/tax/businesses/topics/gst-hst-businesses/digital-economy-gsthst/confirming-simplified-gst-hst-account-number.html. If a non-resident supplier appears only on the Simplified list and not in the standard registry, they cannot charge GST on B2B supplies to Canadian GST-registered businesses — only on B2C supplies. For B2B input tax credit claims, verify that the supplier holds a standard GST registration.

What happens if I claim an ITC based on a supplier's invoice but the supplier's GST number was not registered on the transaction date?

You may lose the input tax credit. Under the Excise Tax Act, you can only claim an ITC on GST paid to a registered supplier. If the CRA audits your ITC claims and finds that the supplier's GST number was not registered on the invoice date — confirmed via the GST/HST Registry's transaction date feature — the CRA will disallow the ITC and may assess penalties and interest. The CRA's position is that the payer is responsible for verifying the supplier's registration status at the time of the transaction. Keeping a screenshot or printout of the GST/HST Registry confirmation for each supplier at the time of transaction is recommended audit documentation.

Does Canada's GST number have a checksum or format validation I can run before querying the CRA registry?

The standard Canadian GST/HST number is a 9-digit Business Number (BN) followed by 'RT' and a 4-digit account identifier (e.g. 119278877 RT 0001). The 9-digit BN does not have a publicly documented checksum algorithm — unlike many European VAT numbers. Format validation is limited to: (1) confirming 9 digits for the BN; (2) confirming the RT suffix for GST accounts (RP for payroll, RC for corporate tax, etc.); (3) ensuring the number is not all zeros or a known invalid placeholder. Because there is no checksum, format validation alone cannot detect miskeyed BNs — the CRA registry query is the only authoritative confirmation.

How to verify GST in Canada?

GST verification on GST/HST Registry

You can check the validity of a GST or HST number on the Canada Revenue Agency website for free. You can access the GST lookup service here. Using this tool you can search for a company by the GST or HST number. You are also required to submit the full business name and a transaction date to search. You will be required to accept the terms and conditions on this page before you can access the search page.

GST lookup - Canada

Example GST: 119278877 (University of Ottawa), 700561103 (Google Asia Pacific Pte. Ltd.)

A successful verification of the GST on the GST registry lookup tool will return the following details

GST/HST number
Business name
Transaction date
Result: "GST/HST number registered on this transaction date"

Successful GST Verification

Simplified GST account number

The list of businesses registered under simplified GST rules applicable for digital businesses is listed here.

For more details on Canadian tax identifiers, see our Canada Tax ID Guide.

Frequently Asked Questions

Why does the GST/HST Registry require a business name and transaction date — can't I look up by number alone?

The CRA requires all three fields as a privacy and security measure. The transaction date requirement is especially important for compliance: it confirms the supplier was GST-registered on the specific date of your transaction. A supplier may have been registered at invoicing time but deregistered later — or vice versa. If the supplier's name in the registry differs from their invoice (legal name vs. trading name), the lookup may fail — ask for their exact CRA-registered legal name. ^[1]

What is the difference between a GST number, HST number, and QST/PST number?

Canada has a dual sales tax system. The federal GST (5%) applies nationwide. In harmonized provinces, GST and provincial tax are collected together as HST: Ontario (13%), Nova Scotia (15%), New Brunswick (15%), Newfoundland and Labrador (15%), PEI (15%). Non-harmonized provinces levy separate taxes: QST (Quebec, 9.975%) requires a separate QST registration number; PST (BC, Saskatchewan, Manitoba) requires provincial registration; Alberta has no provincial sales tax. A supplier in Quebec must have both a federal GST number and a QST number. ^[1]

My supplier is a non-Canadian digital services provider — do they need a standard or Simplified GST registration?

Non-resident digital service providers (streaming, SaaS, app stores) may use the Simplified GST/HST framework rather than standard registration. Simplified registrations have reduced administrative burden but cannot charge GST on B2B supplies to Canadian GST-registered businesses — only on B2C supplies. For claiming input tax credits on B2B purchases, verify the supplier holds a standard GST registration (not just a Simplified one) via the CRA standard registry. ^[1]

What happens if I claim an ITC on a supplier whose GST number was not registered on the transaction date?

You may lose the input tax credit. Under the Excise Tax Act, you can only claim an ITC on GST paid to a registered supplier. If the CRA audits and finds the supplier's GST was not active on the invoice date, the ITC is disallowed and penalties plus interest may apply. The CRA holds the payer responsible for verifying supplier registration status at the time of each transaction. Keep a screenshot of the GST/HST Registry confirmation for each supplier as audit documentation. ^[1]

The GST/HST Registry shows my supplier's number as not found — but they insist they are registered. What could cause this?

Several causes: (1) Name mismatch — use the exact legal name from the supplier's articles of incorporation; (2) Recent registration — new registrations can take 3–10 business days to appear; (3) Deregistration — the supplier may have voluntarily or involuntarily deregistered; (4) Simplified registration — non-resident suppliers on the Simplified framework are on a separate list at canada.ca. Request a copy of the supplier's CRA GST registration confirmation letter as backup documentation. ^[1]

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GST verification on GST/HST Registry​

Simplified GST account number​

Frequently Asked Questions​

Why does the GST/HST Registry require a business name and transaction date — can't I look up by number alone?​

What is the difference between a GST number, HST number, and QST/PST number?​

My supplier is a non-Canadian digital services provider — do they need a standard or Simplified GST registration?​

What happens if I claim an ITC on a supplier whose GST number was not registered on the transaction date?​

The GST/HST Registry shows my supplier's number as not found — but they insist they are registered. What could cause this?​