Business number and CRA program accounts: RC, RP, RT and RZ explained

Almost every Canadian business owner has stared at a fifteen-character string on a CRA notice and wondered what the letters in the middle mean, or opened a payroll account they did not need, or discovered in year three that they should have had an information-returns account since year one. None of it is complicated once you see the structure. This guide sets out how the business number is built, what each program account is for, and when you actually need one.

What the business number is

A business number (BN) is the standard identifier for your business or legal entity. It is not only a CRA number: you need it to interact with provincial or territorial, municipal and other federal programs, which is why it turns up on things that have nothing to do with tax. It is unique, it is nine digits, and it belongs to the entity rather than to any one filing obligation.

If your business is unincorporated, you only need a BN when you register for CRA program accounts. Any newly registered program accounts are simply added to the BN you already have — you do not accumulate business numbers as you add obligations. You may need a new BN in certain situations, most commonly where a genuinely new legal entity comes into existence.

How a program account number is built

When you register for a CRA program account such as GST/HST or payroll, a program identifier and a reference number are added to your existing BN. Together they form your CRA program account number, and that is what you use to report the relevant activity. The three parts are:

• your unique nine-digit BN;
• a two-letter program identifier indicating the account type; and
• a four-digit reference number identifying program accounts of the same type.

The reference number is the part people find confusing, and it exists for a genuine reason: a business can hold more than one account of the same type. A company running two distinct payrolls can have RP0001 and RP0002 under the same BN. Most small businesses have exactly one of each and never think about it — until a second one is opened by mistake and remittances start arriving against an account nobody is filing for.

The program accounts

The point of the table is not to register for everything on it. It is to recognise which of these your actual activities trigger, and to notice when a new activity creates a new obligation part-way through a year.

RC: corporation income tax

The corporation income tax account is where the T2 return lives. Most owners never register for it deliberately, because it usually arrives with the incorporation. If you incorporate federally through Corporations Canada, once the incorporation is approved you get a business number and your RC program account without registering separately with the CRA. Several provinces do the same — incorporate provincially in one of them and the BN and RC account come as part of the process.

What does not come automatically is everything else. GST/HST and payroll are registered with the CRA afterwards, and the gap between “I incorporated” and “I am registered for what I need” is where most first-year compliance problems start. The just-incorporated checklist walks through the full sequence.

RP: payroll deductions

You need a payroll account before your first payroll run if the corporation has employees — and that includes an owner-manager taking a salary rather than dividends. It is not required if the only payments to the owner are dividends, or if the people you pay are genuinely independent contractors rather than employees, though that second distinction is one worth testing rather than assuming.

The RP account carries real risk, because unremitted source deductions are not the corporation’s money and directors can be held personally liable for them. The mechanics of withholding, remitter frequency and year-end slips are covered in the guide to payroll remittances and the RP account.

RT: GST/HST

The GST/HST account is the one with an actual numeric trigger. If you do not exceed $30,000 over four consecutive calendar quarters you are a small supplier and do not have to register, although you may register voluntarily if you make taxable supplies in Canada. Exceed $30,000 in a single calendar quarter and you are no longer a small supplier: you have to charge GST/HST on the supply that took you over, and your effective registration date is no later than the day of that supply.

There is a third case people miss. If you exceed the threshold over the previous four or fewer consecutive quarters but not in a single quarter, you stop being a small supplier at the end of the month following the quarter in which you exceeded it. Registering early is often sensible anyway, because registration is what allows input tax credits on your costs. The full timing rules are in the GST/HST registration guide.

RZ: information returns

The information returns account is the one most often missing from a file that otherwise looks tidy. It is used for returns that report payments rather than your own income — most visibly, in construction, the T5018 statement of contract payments. Because the obligation is separate from the T2 and the GST/HST return and runs on its own deadline, it does not surface through the usual filing rhythm; nothing prompts you. The T5018 guide covers who has to file and when.

When you need a second account, and when you do not

The four-digit reference number exists because one entity can legitimately hold several accounts of the same type, but that is much rarer than the number of duplicate accounts in the wild would suggest. Genuine reasons include separately administered payrolls or distinct divisions that need their own filing streams. Accidental reasons are far more common: an owner registers online, does not realise an account already exists, and creates a second one that nobody then files for.

The cost of a stray account is not theoretical. The CRA expects returns on every open program account, and a nil obligation is still an obligation — unfiled returns on an account you did not know you had generate notices, and in the payroll case they generate arbitrary assessments. If duplicates exist, they should be closed deliberately rather than ignored.

The other event that prompts a second look is a change in the legal entity itself. Adding a program account to an existing BN is routine; a genuinely new legal entity is a different matter and may need its own BN. Incorporating a business that previously operated as a sole proprietorship is the classic case, and the accounts do not simply migrate because the trading name did not change.

Keeping track of what you have

The practical control is My Business Account, which shows every program account registered under your BN, their status, balances and filing history in one place. Two checks are worth doing once a year: that every account listed is one you actually need and are filing for, and that every activity you carry on has an account behind it. Dormant accounts left open still expect returns, and the CRA will chase a nil filing on an account you forgot existed. The My Business Account setup guide covers getting access.

Getting it right

Program accounts are administrative, which is exactly why they get neglected — there is no deadline for noticing that you needed one. The simplest approach is to map your activities to accounts once, at set-up, and re-check when something changes: a first employee, a first subcontractor, crossing the GST/HST threshold, a second payroll. Getting that map right at the start avoids the two common outcomes: filings owed on accounts nobody opened, and returns expected on accounts nobody needed.

This article is general information for Canadian business owners and is current as of July 2026. CRA program account types and registration processes change — confirm the current position on canada.ca or through My Business Account before registering. It is not tax advice; please speak with a CPA before acting on anything here.