The CO-17: who files it, when, and how

The short answer

The CO-17 is the corporation income tax return in Quebec. A corporation with an establishment in Quebec files it with Revenu Québec every year, even with no income, within six months after the end of its taxation year. The balance of tax is due sooner: within two months after the end of the year.

Who has to file it

Any corporation that had an establishment in Quebec at any time in the year. Revenu Québec takes the word broadly. A corporation has an establishment in Quebec in cases such as these:

• it has a fixed place in Quebec where it carries on its business, such as an office, a branch, a warehouse or a workshop;
• it has no fixed place, but its main place of business is in Quebec;
• it has no establishment, and its head office, as set out in its articles, is in Quebec;
• it owns a building in Quebec that it uses mainly to earn rent;
• it carries on business in Quebec through an employee or agent who has general authority to sign contracts for it;
• it uses a substantial amount of machinery or equipment in Quebec;
• it's a member of a partnership that has an establishment in Quebec.

There are other cases, such as a non-resident corporation that disposes of taxable Quebec property.

A year with no income changes nothing. The corporation files its CO-17 whether or not it has tax to pay, and an inactive corporation encloses a balance sheet showing its financial position at the end of the year. We explain it in A year with no income: do I still have to file?

The dates to remember

For a corporation whose taxation year ends on December 31, 2026:

• by the end of February 2027, the year's balance of tax is paid to Revenu Québec. After that date, interest runs, compounded daily;
• by June 30, 2027, the CO-17 is filed, with the corporation's complete financial statements: balance sheet, income statement, statement of retained earnings, cash flow statement and notes.

A late CO-17 brings a penalty of 5% of the unpaid tax, plus 1% for each complete month late, up to 12 months.

Watch for one difference from the federal rules. A Canadian-controlled private corporation that meets certain conditions tied to the small business deduction can have three months to pay the balance of its T2. Quebec has no such extension: the CO-17 balance is due after two months, even for that corporation.

Is there a short version?

Revenu Québec's guide provides none for small businesses: every corporation files the full CO-17, with its financial statements. Forms numbered CO-17S, such as CO-17S.4 on losses, are schedules, not a short version. Non-profit organizations can file the CO-17.SP, and an organization that was a registered charity for the whole year files the TP-985.22.

How to file it

The CO-17 is completed with commercial software authorized by Revenu Québec. For taxation years beginning on or after January 1, 2024, every corporation must file it online, whatever its gross revenue. Only a few are exempt, such as insurers, non-resident corporations and tax-exempt corporations (non-profits, for example), and they are the only ones that can still mail it in. A corporation that doesn't meet the requirement can face a penalty.

The corporation can file it itself with commercial software, as long as it's enrolled in clicSÉQUR, or have a person accredited by Revenu Québec file it. A return filed online goes with the Canada Revenue Agency's General Index of Financial Information (GIFI) form.

The CO-17 and the T2

In Quebec, a corporation files two income tax returns: the T2 with the Canada Revenue Agency, and the CO-17 with Revenu Québec. Both have the same six-month deadline, and the T2 is also filed electronically, with some exceptions. Elsewhere in Canada it's different: in Ontario and British Columbia, the provincial tax is calculated on the T2, with no separate provincial return, and in Alberta, the corporation also files the AT1.

How we handle it

With our income tax add-on, we prepare your corporation's T2 and CO-17 from your books, and file them electronically once you approve them. Professional representation and electronic filing authorized by Revenu Québec. You know ahead of time what's owed, and when. It's all on our Incorporated businesses page.