If you own the business you work in, you have planning options an ordinary employee does not. You can choose the legal structure your income flows through, you can pay reasonable wages to family members who actually work, and you can defer tax by leaving surplus inside a corporation. Used correctly and within the rules, these tools meaningfully lower the tax a family pays as a unit. Used carelessly, they trip anti-avoidance rules that can be punishing. This guide covers both sides.
Why a corporation defers tax
A corporation is its own legal person, separate from its shareholders. For an owner whose business throws off more cash than the family spends, that separateness is the heart of the tax advantage. Active business income earned inside a Canadian-controlled private corporation (CCPC) — up to the small business limit, currently $500,000 a year — is taxed at a much lower rate than the same income earned personally.
Consider a simplified example. Suppose $50,000 of surplus is earned. Taxed personally at a 50% rate, $25,000 goes to tax and $25,000 remains. Earned in a corporation taxed at, say, 15%, only $7,500 goes to tax immediately. The difference — roughly $17,500 — stays in the corporation, where it can be invested or used to grow the business. The tax is not erased; it is deferred until the money is eventually paid out to the shareholder and taxed in their hands. But deferral itself has real value: a dollar of tax paid years from now, with money that has been working in the meantime, costs less than a dollar of tax paid today.
A corporation does more than defer tax. It creates a liability shield: shareholders are generally insulated from claims against the company, with limited exceptions such as unremitted GST/HST and payroll source deductions. If you take on co-owners, put a unanimous shareholders' agreement in place early, while everyone is still on good terms — it governs share transfers, decision thresholds, and dispute resolution.
Paying reasonable wages to family
One of the cleanest ways to lower a family's overall tax is to pay a reasonable salary to a spouse or children who genuinely do work for the business. Income shifts from a high-bracket earner to a lower-bracket family member, raising the family's combined after-tax income.
The example from the book is illustrative. A parent in a 53% bracket would pay about $10,600 of tax on $20,000 of income. If instead the business pays two teenagers $10,000 each for genuine part-time work, and the teenagers have no other income, they may pay little or no tax — keeping far more of the money in the family. The savings can fund the very activities the parent would otherwise have paid for with after-tax dollars.
Two conditions are non-negotiable. First, the wage must be reasonable under section 67 of the Income Tax Act — pay what you would pay a stranger to do the same job. If a task is worth $20 an hour, paying a family member $50 an hour for it invites a denial on audit. Second, the work has to be real; keep timesheets and a record of what was actually done. (And no, it is not reasonable to "employ" a three-year-old as a model.)
When a partnership fits better than a corporation
A corporation is the right vehicle most of the time, but not always. When two or more people carry on business together intending to profit, they form a partnership by default. A general partnership lets people in different tax brackets work together without first splitting income that has already been taxed at the corporate level — the profit flows straight to the partners and is taxed at each partner's own rate.
Where family members genuinely contribute, a partnership can let a higher-bracket partner and a lower-bracket partner share the income and the tax. Be clear-eyed about the trade-off: in a general partnership each partner can bind the others, and partners are jointly and severally liable for the partnership's debts. A limited partnership separates a managing general partner from passive limited partners and is common for holding real estate, but it requires formal registration.
The traps: attribution rules and TOSI
Income splitting only works inside guardrails. Two sets of rules exist precisely to stop the simplest forms of it.
The attribution rules (sections 74.1 to 74.5 and 75.1 of the Income Tax Act) generally attribute investment income — and in some cases capital gains — back to the person who transferred or loaned property to a spouse or a minor child. Give your lower-income spouse investment funds, and the investment income is usually taxed back to you, not them. A properly documented loan at the prescribed interest rate can avoid spousal attribution.
The tax on split income (TOSI), in section 120.4, broadened the rules dramatically in 2018 to limit "income sprinkling" through private corporations. TOSI can apply the highest marginal rate to dividends, certain capital gains, and similar amounts received by a family member from a related business. There are exceptions — a reasonable return for genuine contributions, an excluded business in which the person is actively engaged (a 20-hour-per-week benchmark is often used), excluded shares for those 25 and older meeting ownership and income tests, and age-based carve-outs. But the exceptions are technical, and several are unavailable to professional corporations.
The practical takeaway: paying a reasonable salary for real work is on solid ground. Anything more elaborate — sprinkling dividends, transferring shares to family, shifting investment income — should be reviewed against the attribution and TOSI rules before you act.
Where to go from here
Owner-manager planning rewards owners who treat structure as a deliberate choice rather than an afterthought. For the deduction side of the equation, see our guide to deducting business expenses the right way; for succession and exit planning, see deferring tax with rollovers and an estate freeze.
This guide draws on Dale Barrett's book Pay WAY Less Tax!, a plain-language collection of tax-saving tips and strategies for Canadians. The book is general information, not legal advice; the rules change often, so confirm the current treatment for your own situation before acting.