Business Number (CRA)

The Business Number (BN) is the CRA's 9-digit identifier for a business entity. It functions like a social insurance number for a business: it is unique to that entity and is used across multiple federal tax programs.

The BN itself (9 digits, e.g., 123456789) is the root identifier. Each CRA program account is a separate extension of the BN:

• RT — HST/GST account (e.g., 123456789 RT 0001)
• RC — Corporate income tax account (e.g., 123456789 RC 0001)
• RP — Payroll deductions account (e.g., 123456789 RP 0001)
• RM — Import/export account (e.g., 123456789 RM 0001)
• RZ — Information returns (e.g., T5, T4A filers)

A business may have multiple accounts of the same type — for example, a company with operations in multiple divisions may have more than one payroll account (RP 0001, RP 0002).

The BN is assigned when a business first registers with the CRA or, for corporations, is often issued automatically when a federal or Ontario corporate income tax account is first required.

The HST/GST program account (identified by the suffix RT) is the most commonly used CRA account for Ontario businesses. It is used to collect and remit Harmonized Sales Tax (HST) under the Excise Tax Act, RSC 1985, c E-15.

Mandatory registration threshold: A business must register for an HST account when its commercial revenues (taxable supplies) exceed $30,000 in a single calendar quarter or in four consecutive calendar quarters. This $30,000 threshold applies per person (entity) — not per business activity.

Voluntary registration: Businesses with revenues below $30,000 may register voluntarily. This is advantageous because registered businesses can claim input tax credits (ITCs) — refunds of the HST paid on business purchases and expenses. For a new business investing in equipment or leasehold improvements, voluntary registration can result in a meaningful HST refund.

Small supplier exception: A business that qualifies as a small supplier (revenues below the $30,000 threshold) does not charge HST and cannot claim ITCs. Once the threshold is exceeded, registration is mandatory from the date it is exceeded (or the beginning of the following month for the quarterly threshold).

Reporting periods: The frequency of HST returns depends on annual revenues: - Annual (revenues under $1.5 million) - Quarterly (revenues $1.5 million to $6 million) - Monthly (revenues over $6 million)

Businesses can elect a more frequent filing period than required.

Ontario-specific: Ontario adopted the HST (combining the federal 5% GST with the provincial component to create a 13% combined rate) effective July 1, 2010. Ontario HST is administered entirely by the CRA, unlike the pre-2010 RST system.

Zero-rated and exempt supplies: Not all supplies are subject to HST. Zero-rated supplies (taxable at 0%, allowing ITCs) include basic groceries, prescription drugs, and exports. Exempt supplies (no HST, no ITCs) include residential rent, most healthcare services, and educational services.

The corporate income tax account (RC) is the account through which a corporation files its T2 Corporation Income Tax Return and pays corporate income tax.

Who needs it: Every Canadian corporation (including Ontario corporations under the OBCA and federal corporations under the CBCA) must file a T2 return for every taxation year, even if there is no tax payable and even if the corporation was inactive. The RC account is typically assigned automatically when the corporation first comes to the CRA's attention.

T2 filing deadline: A corporation's T2 return must be filed within 6 months after the end of its fiscal year. However, taxes are due within 2 months of year-end for most corporations (3 months for Canadian-controlled private corporations eligible for the small business deduction, in the year they are claiming SBD).

Instalments: Corporations are generally required to make monthly income tax instalment payments based on their prior-year tax liability. CCPCs with a modest tax liability may use quarterly instalments.

Ontario corporate tax: Ontario corporate income tax is assessed federally through the CRA for taxation years ending after December 31, 2008. Prior to that, Ontario had its own provincial tax return (CT23). Since 2009, a single T2 return is filed with the CRA, which then transfers Ontario's share to the province.

Corporation number vs. BN: A corporation has both an Ontario corporation number (assigned by the Ministry of Public and Business Service Delivery at incorporation) and a BN (assigned by the CRA). These are different numbers and serve different purposes. The corporation number is used for provincial filings (annual returns, corporate changes); the BN is used for federal tax filings.

A payroll account (RP) is required by any business that employs workers and pays them employment income from which deductions must be withheld and remitted to the CRA.

Who needs it: Any business that pays salary, wages, bonuses, or taxable benefits to employees. Directors' fees and certain employment-like arrangements can also require payroll account registration.

What must be withheld: Employers must withhold from employee paycheques: - Federal and provincial income tax (based on TD1 forms submitted by employees) - Canada Pension Plan (CPP) contributions (employee's share) - Employment Insurance (EI) premiums (employee's share)

In addition, the employer must remit: - CPP employer contributions (equal to the employee's CPP contribution) - EI employer premium (1.4x the employee's EI premium)

Remittance schedule: The frequency of remittances depends on the employer's average monthly withholding amount: - Quarterly remitters: average withholdings under $1,000/month (threshold for new/small employers) - Regular (monthly) remitters: average $1,000-$24,999/month - Accelerated remitters: average $25,000+/month

T4 slips: By February 28 each year, employers must issue T4 slips to employees and file a T4 Summary with the CRA. The T4 summary is filed under the payroll account (RP).

Director liability: Directors of a corporation are personally liable for unremitted payroll source deductions if the corporation fails to remit — a critical risk that applies equally to directors of NFPs, small businesses, and large corporations.

An import/export account (RM) is required for businesses that import commercial goods into Canada or export goods that require customs documentation.

Import account: Required when a business imports goods into Canada for commercial purposes. The importer of record must have a valid BN with an RM account registered with the Canada Border Services Agency (CBSA). Without an RM account, goods cannot be cleared through Canadian customs.

Export account: Required for certain exports that need to be reported to the CBSA, including goods with a value over $2,000 and goods subject to export controls.

CBSA coordination: While the BN/RM account is a CRA registration, it is used in the CBSA's systems for customs reporting. The CBSA issues its own importer/exporter account numbers that use the BN as their base.

When Ontario businesses need it: Most purely domestic Ontario businesses do not need an RM account. It becomes relevant when a business begins: (1) buying goods directly from foreign suppliers (e.g., importing inventory from Asia or Europe); (2) selling goods to foreign customers requiring customs documentation; or (3) participating in trade shows or temporary imports.

CARM (CBSA Assessment and Revenue Management): The CBSA has implemented the CARM system, which requires importers to register directly on the CARM client portal using their BN-RM account. Importers and their customs brokers must be registered on CARM to release commercial goods.

There are several ways to register for a CRA Business Number and program accounts:

1. Online (Business Registration Online — BRO): The CRA's Business Registration Online (BRO) portal allows businesses to register for a BN and most program accounts (HST/RT, payroll/RP, import/export/RM) online at no charge. Access BRO through the CRA website.

2. By telephone: Call the CRA's Business Registration line at 1-800-959-5525. A CRA agent will register the business and assign a BN and program accounts during the call.

3. By mail or fax: Complete Form RC1 (Request for a Business Number and Certain Program Accounts) and mail or fax it to the applicable CRA tax centre.

4. Through a lawyer or accountant: Lawyers incorporating Ontario companies often register the corporation's BN and initial CRA accounts as part of the incorporation process.

When does registration happen? - For corporations, the RC (corporate income tax) account is typically assigned when the T2 return is first filed or when the CRA becomes aware of the corporation - For HST/RT, registration should occur as soon as the $30,000 threshold is exceeded (or immediately upon incorporation for most businesses expecting to exceed it) - For payroll/RP, registration should occur before the first payroll is run

Information needed to register: Legal name of the business, operating (trade) name (if different), business address, nature of business activities, effective date of first business activity, and the name and SIN of the business owner (for sole proprietors and partnerships) or the corporation number and date of incorporation (for corporations).

Ontario business owners often confuse the CRA Business Number with the Ontario corporation number. These are entirely separate identifiers:

Ontario Corporation Number: - Assigned by the Ontario Ministry of Public and Business Service Delivery when a corporation is incorporated under the OBCA - Used for provincial filings: annual returns, articles of amendment, applications for dissolution, etc. - Format: typically 7 digits (e.g., 1234567) - Not used for CRA tax filings

CRA Business Number: - Assigned by the Canada Revenue Agency - Used for all federal tax accounts: HST, corporate income tax, payroll, import/export - Format: 9 digits (e.g., 123456789) - Not assigned by the Ontario government

For Ontario corporations, both numbers will be assigned. Federal CBCA corporations also receive a federal corporation number from Corporations Canada, separate from both the Ontario corporation number and the CRA BN.

Practical tip: When filling out Ontario provincial forms (e.g., annual return), use the Ontario corporation number. When filing with the CRA (T2, HST return, payroll), use the BN.

Rania incorporates Rania Design Inc. under the OBCA on January 15, 2026. The province assigns Ontario corporation number 9876543.

Within weeks, Rania: 1. Registers for a CRA Business Number through BRO — she receives BN 123456789 2. Opens an HST account (RT) immediately, because she expects to bill corporate clients well over $30,000 per year 3. Does not open a payroll account yet — she is the sole director and has not hired any employees 4. Does not open an import/export account — her business is domestic digital design services

By March, she hires an employee. She registers for a payroll account (RP) before running her first payroll and sets up payroll software to calculate and remit source deductions monthly.

Her first T2 return is due within 6 months after her December 31, 2026 fiscal year-end — by June 30, 2027. Corporate income tax is due by March 31, 2027 (3-month deadline for CCPCs claiming SBD).