Owning a Canadian business through a corporation opens up planning choices that an employee never has to think about. How you pay yourself, where you keep retained earnings, who owns the shares, how you eventually sell — each is a decision with a tax consequence, and the decisions compound over the life of the business. This guide walks through the main moving parts of a business owner's tax plan so you can see how they fit together. It is general information, not advice on your particular facts, but it should help you ask sharper questions of your own advisors.
Start with integration
The Canadian tax system is built on a principle called integration. The idea is that income earned through a corporation and then paid out to you should bear roughly the same total tax as if you had earned it personally — no better, no worse. Integration is never perfect, and the small gaps it leaves are exactly where planning lives. When you understand that the corporate tax paid and the personal tax on a later dividend are meant to add up to roughly the personal rate, the choices below stop looking like tricks and start looking like what they are: managing the timing and the character of income within a system that is trying to reach the same destination either way.
The remuneration mix: salary, dividends, or both
The first recurring decision is how to extract money from the corporation. The two main routes are salary and dividends, and most owner-managers use some blend of the two.
- Salary is deductible to the corporation, is taxed in your hands as employment income, generates RRSP contribution room, and requires CPP contributions (both the employer and employee halves, since you are both).
- Dividends are paid out of after-tax corporate income, are not deductible to the corporation, are taxed at lower personal rates because of the dividend tax credit, generate no RRSP room, and attract no CPP.
Neither route is universally better. Salary creates RRSP room and CPP entitlement and can be useful where you want to build registered savings or qualify for income-tested benefits; dividends avoid CPP and can simplify the payroll burden. The right blend depends on your cash needs, your appetite for RRSP versus corporate savings, your CPP views, and the corporation's income level. We work through the trade-off in detail in our companion piece on salary versus dividends.
Income splitting and the TOSI rules
For decades, paying dividends to lower-income family members was a standard way to reduce a family's overall tax. Since 2018, the tax on split income (TOSI) rules have sharply restricted this. TOSI applies the top marginal rate to "split income" received by a related individual from a private corporation, unless an exclusion applies.
The exclusions are the whole game. The most important are the excluded business exclusion (for family members who work an average of at least 20 hours a week in the business during the year, or did so in any five prior years), the excluded shares exclusion (broadly, for a shareholder aged 25 or older who owns at least 10% of the votes and value of a corporation that is not a professional corporation and earns less than 90% of its income from services), and the exclusions for individuals aged 65 or older and their spouses, which mirror pension-splitting policy. Where an exclusion applies, dividends to that family member are taxed at their own graduated rates; where none applies, TOSI claws the benefit back. Income splitting is still possible, but it has to be built deliberately around the exclusions rather than assumed.
The holding company
Many owner-managers eventually insert a holding company above their operating company. A holdco owns the shares of the operating company, and surplus cash is moved up to the holdco as inter-corporate dividends, which are generally tax-free between connected Canadian corporations under section 112.
A holdco does several jobs at once. It moves retained earnings out of the operating company, away from the operational creditors and the day-to-day risk, which is a form of creditor protection. It creates a place to hold passive investments separate from the active business. And it positions the group for a future sale, because a buyer usually wants to buy a clean operating company without years of accumulated investment assets inside it. The trade-offs are the extra compliance cost of a second corporation and the passive-investment-income rules, which can reduce the operating company's access to the small-business deduction where passive income inside the associated group climbs above defined thresholds.
The lifetime capital gains exemption
One of the most valuable features of owning an active Canadian business is the lifetime capital gains exemption (LCGE) on the sale of qualified small business corporation (QSBC) shares. The LCGE shelters a substantial amount of capital gain — over one million dollars per individual, indexed — when you sell shares that meet the QSBC tests.
The tests are technical and easy to fail by accident. Broadly, at the time of sale the shares must be of a small business corporation using all or substantially all of its assets in an active business carried on primarily in Canada; for the 24 months before the sale, more than 50% of the corporation's assets must have been so used; and the shares must have been owned by you or a related person throughout that 24-month period. The asset tests are where plans come undone: a corporation that has accumulated too much passive cash or investments can be "contaminated" and fall offside. Purification — moving the non-active assets out, often to a holdco, well before a sale — is what keeps the shares qualifying. Because the holding-period and asset tests look backward, purification is something to plan years ahead, not in the weeks before a closing.
RDTOH and the CDA: the two accounts every owner should know
Two notional tax accounts govern how investment income flows out of a corporation efficiently, and owner-managers benefit from understanding them at least in outline.
RDTOH — the refundable dividend tax on hand. When a corporation earns investment income (interest, certain dividends, taxable capital gains), part of the corporate tax it pays is refundable. That refundable portion accumulates in the RDTOH account and is refunded to the corporation when it pays a taxable dividend to shareholders. The mechanism exists to support integration: investment income is taxed at a high rate inside the corporation to discourage indefinite deferral, and the refund returns the excess when the income is finally distributed. (Since 2019, RDTOH is split into an eligible and a non-eligible pool, which affects the type of dividend that triggers the refund.)
CDA — the capital dividend account. The CDA is a notional account that tracks the tax-free half of capital gains, certain life-insurance proceeds, and capital dividends received. A corporation can elect to pay a capital dividend out of its CDA balance entirely tax-free to Canadian-resident shareholders. The CDA is one of the most valuable balances in a private corporation, and it has to be tracked precisely — paying a capital dividend that exceeds the CDA balance triggers a punitive penalty tax, so the balance should be confirmed before any capital dividend is declared.
Year-end planning
Much of a business owner's tax planning happens in the weeks before the corporate year-end, when the year's results are visible but the books are not yet closed. Recurring year-end moves include: finalizing the salary/dividend/bonus mix for the year (a bonus accrued in the corporate year and paid within 179 days is deductible in the earlier year); paying out enough taxable dividends to recover available RDTOH; declaring a capital dividend where there is CDA room; making or topping up RRSP and, where eligible, individual pension plan contributions; reviewing whether the small-business-deduction limit is being eroded by passive income or by association with other corporations; and confirming the active-asset position if a sale is on the horizon. None of these works as an afterthought in the following spring — they have to be done before the year-end closes.
How the pieces fit together
The themes above are not separate silos; they interact. The remuneration mix affects RRSP room and the corporation's retained earnings, which affects how much passive income accumulates, which affects both the small-business deduction and the QSBC purity that the LCGE depends on. A holdco changes where surplus sits and how RDTOH and CDA balances are managed across the group. An estate freeze layered on top fixes today's value and shifts growth to a family trust, which reintroduces the TOSI analysis on any dividends paid through the trust. A coherent plan looks at the whole structure rather than optimizing one piece at the expense of another.
How the work gets done
In a typical engagement, the lawyer and the client's accountant divide the work: the accountant handles the financial statements, the corporate return, and the mechanical elections, while the lawyer handles the structure, the share terms, the trust documentation, and the legal record that has to line up with the tax filings. Barrett Tax Law is a Canadian boutique tax law firm whose practice is concentrated on corporate tax planning and reorganizations alongside CRA disputes and Tax Court litigation, and it coordinates with clients' existing accountants rather than displacing them. If you are weighing how to pay yourself, whether to add a holdco, or how to position a business for an eventual sale, the first consultation focuses on your structure and the realistic options for it.