This search finds a federal corporation's business number, the first nine digits of its GST/HST number. It cannot tell you whether the business is registered for GST/HST: only the CRA's registry confirms that.
In short
- The CRA's GST/HST Registry confirms whether a supplier was registered for GST/HST on the date of a transaction.
- You need three things: the first nine digits of the supplier's GST/HST number, the business name on the invoice, and the transaction date.
- It only confirms a number you already have. It is not a search engine, so it cannot find a number from a business name.
- A supplier must show its GST/HST number on invoices of $100 or more for the buyer to claim input tax credits.
How to do a GST number lookup in the CRA registry
Find the number on the invoice
Take the GST/HST registration number from the supplier's invoice, receipt or contract. If the supplier has not given one, ask for it: under the Excise Tax Act, a supplier must give a buyer, on request, the details the buyer needs to support a claim.
Open the CRA's GST/HST Registry
Go to Confirming a GST/HST account number on the CRA website, choose to search, and accept the terms of use. The registry is open Monday to Saturday and closed on Sundays.
Enter the search details
Enter only the first nine digits of the number, with no letters; the business name as the supplier's invoice or sign shows it (its legal, operating or trading name); and the transaction date from the invoice.
Read and keep the result
The registry shows the supplier's registration status on that date, or says that the details entered do not match its records. Print the search details screen for your files.
What a GST/HST account number looks like
A GST/HST account number is the supplier's nine-digit business number, the letters RT, and a four-digit reference number: the CRA's example is 123456789 RT 0001. The first nine digits are the business number; the business number lookup finds a federal corporation's by name.
The 15-character number on Corporations Canada's federal search, such as 123456789RC0001, is the corporation income tax account, not the GST/HST number: RC is income tax and RT is GST/HST. A corporation has an RT account only if it registered for GST/HST. Digital businesses outside Canada registered under the simplified GST/HST system appear on a separate public CRA list.
Supplier invoices and the input tax credit claim
Once registered, a GST/HST registrant must charge the GST or HST on its taxable sales. To claim an input tax credit (ITC), a buyer needs the supplier's GST/HST registration number on any invoice of $100 or more. Under $100, the supplier's name, the date and the total are enough. At $500 or more, the buyer's name, a description of the goods or services and the payment terms are added. These thresholds apply from April 20, 2021; older CRA pages still show $30 and $150.
If a supplier will not give its number, call the Canada Revenue Agency's Business Enquiries line, 1-800-959-5525, to confirm whether it has a GST registration.
Quebec: checking a QST number
Quebec's sales tax (QST) has its own registration number: ten digits, the letters TQ and four more digits. Revenu Québec checks it with its free Validate a QST registration number service, which asks only for the number. A QST number beginning with NR belongs to a supplier outside Quebec registered under Revenu Québec's specified system, and buying from it gives no input tax refund. Nine-digit QST numbers of selected listed financial institutions cannot be checked online; the CRA confirms them by phone. A business located in Quebec deals with Revenu Québec for the GST/HST too.
GST verification: what this site can and cannot tell you
This site shows each federal corporation's business number, the first nine digits of any GST/HST number it has, and its legal name, status and registered office from the federal record. It does not know whether a business is registered for GST/HST: the CRA publishes that only for businesses under the simplified system, and its registry results may not be reproduced commercially. Use the CRA's registry for that check. To find your own GST/HST number, see find my GST and HST number.
Frequently asked questions
How do I check a GST number?
Use the CRA's GST/HST Registry on canada.ca. Enter the first nine digits of the number, the business name on the invoice and the transaction date, and it tells you whether the supplier was registered on that date.
How do I find out if a company is GST registered?
Ask the supplier for its GST/HST number, then confirm it with the CRA's GST/HST Registry. If the supplier will not give a number, call the CRA's Business Enquiries line at 1-800-959-5525.
Is a GST number the business number plus RT0001?
Usually. A GST/HST number is the nine-digit business number, RT, and a four-digit reference number, most often 0001. A business has one only if it registered for GST/HST.
Can I look up a GST number by business name?
No. The CRA's registry only confirms a number you already have. You can find a federal corporation's business number by name on this site, but not whether it is registered for GST/HST.
Do I need to put my GST number on my invoices?
Yes, on any invoice of $100 or more, so that a customer who is registered can claim input tax credits. Under $100 it is not required.
How do I check a QST number?
Use Revenu Québec's free Validate a QST registration number service. A QST number is ten digits, the letters TQ and four more digits.
Official sources
- Confirming a GST/HST account number(opens in a new tab)
The CRA's GST/HST Registry: what you need and how to search.
- GST/HST Registry hours of service(opens in a new tab)
When the registry is open, Monday to Saturday.
- Input tax credits(opens in a new tab)
What an invoice must show at $100 and at $500 or more.
- General information for GST/HST registrants (RC4022)(opens in a new tab)
What a GST/HST account number looks like.
- Confirming a simplified GST/HST account number(opens in a new tab)
The public list of businesses registered under the simplified system.
- Validate a QST registration number(opens in a new tab)
Revenu Québec's free check of a QST number.
- Search for a federal corporation(opens in a new tab)
A federal corporation's business number, from Corporations Canada.
This page explains the general rules. It is not tax or legal advice for a particular situation. The Canada Revenue Agency's and Corporations Canada's own pages are the official word; this page was last checked against them on Oct 28, 2026.