When Should You Incorporate Your Business in Ontario? Sole Proprietorship vs. Corporation

Most Ontario businesses start as a sole proprietorship because it is the path of least resistance. The owner starts working, registers a business name if one is used, and reports the income on a personal tax return. Ontario's own guidance for new businesses says as much: a sole proprietorship is easy and inexpensive to set up, and the owner can choose to incorporate later as the business grows.

The harder question is when later arrives. Incorporating too early adds cost and paperwork to a business that may not survive its first year. Incorporating too late leaves the owner personally exposed during the period of fastest growth and can forfeit tax planning that only works with lead time. This article sets out the tests that usually decide the timing. It is general information, not legal or tax advice, and the tax points in particular need an accountant's model of your actual numbers.

The encyclopedia entry on sole proprietorships and the entry on corporations describe each structure on its own. Here the focus is on the moment to move from one to the other.

The Canada Revenue Agency describes a sole proprietor as having no legal status separate from the business, so the business's risks can reach the owner's personal property and assets. Every contract the business signs is the owner's contract. Every debt is the owner's debt. A lawsuit over a defective product, a slip on the premises or a dispute with a client lands on the owner's house and savings.

A corporation changes that starting point. Subsection 92 (1) of the Business Corporations Act provides that shareholders are not, as shareholders, liable for the acts, defaults, obligations or liabilities of the corporation, subject to a handful of statutory exceptions. The exceptions matter. A shareholder who signs a personal guarantee for a lease or a loan is liable on the guarantee. Directors, who in a small company are usually the same people as the shareholders, are personally liable under section 131 for up to six months of unpaid employee wages and up to twelve months of accrued vacation pay, and the Canada Revenue Agency notes that directors can be liable for amounts such as unremitted source deductions. A person remains liable for their own negligence regardless of the corporate form.

The practical test is this: list the ways the business could cause loss to someone else, and ask whether the owner could absorb the worst realistic case personally. A consultant who gives advice to a few clients, carries professional liability insurance and signs small contracts may be comfortable for a while. A contractor with crews on site, a food business, a landlord, an online retailer shipping products or anyone hiring employees usually reaches the point of incorporating on liability grounds before the tax numbers get there.

The second test is financial, and it has nothing to do with gross revenue. It is about how much profit the business earns beyond what the owner takes out to live.

A sole proprietor pays personal tax on the business's entire net income in the year it is earned, whether or not it is spent. A corporation is taxed as a separate taxpayer. Profit retained inside the corporation after corporate tax can fund equipment, inventory, a hire or an investment account without first passing through the owner's personal return. A Canadian-controlled private corporation that qualifies for the small business deduction pays a lower corporate rate on eligible active business income up to its business limit, which is what creates the deferral. The encyclopedia entry on the small business deduction explains the conditions and their limits.

The key word is deferral. When the owner eventually takes the money out as salary or dividends, personal tax applies. If the owner needs every dollar the business earns to pay the mortgage and the groceries, the money comes out immediately, and the corporation offers little tax advantage while adding a second tax return. If the business consistently earns more than the owner draws, the deferral compounds and the corporation starts to pay for itself. The comparison of sole proprietorship and corporate taxation and our guide to paying yourself from a corporation go further. The decision belongs in a spreadsheet prepared by an accountant who knows your province, your family's other income and your spending.

Some businesses incorporate because the market demands it. Large customers often contract only with corporations, procurement portals may require a corporation number, insurers may price coverage differently, and agencies that place contractors frequently insist on an incorporated supplier.

That last situation carries a warning. The Canada Revenue Agency treats a corporation as carrying on a personal services business where the individual doing the work would reasonably be regarded as an employee of the client if the corporation did not exist, and special income tax rules then apply to the corporation. In broad terms those rules deny the small business deduction and sharply limit the expenses the corporation can deduct, which can leave the incorporated contractor worse off than an employee. The factors the agency looks at are the same ones that distinguish employees from independent contractors: control over the work, ownership of tools, the chance of profit and risk of loss, and whether the worker has multiple clients. A contractor with one long-term client who works on the client's premises, on the client's hours, with the client's equipment, should get tax advice before incorporating to satisfy that client. The encyclopedia comparison of contractors and corporations outlines the issue.

Where the business genuinely has several clients, bears its own risk and controls its own work, a client's preference for dealing with a corporation is a legitimate reason to incorporate and often coincides with the liability and tax tests pointing the same way.

Three events almost always justify incorporating before they happen rather than after.

Hiring. Employees bring payroll remittances, workplace safety obligations, employment standards liability and the possibility of wrongful dismissal claims. A corporation contains those obligations, subject to the director liabilities noted above, and gives the business an identity that survives the owner.

Bringing in a partner. Two people can run an unincorporated business as a partnership, but a partnership exposes each partner to the debts of the other and makes it awkward to divide ownership unequally or to buy a partner out. Shares solve those problems cleanly. A corporation lets the founders hold different percentages, issue shares to a new participant later and write a shareholder agreement that governs decision-making, exits and deadlock. The encyclopedia entry on partnerships describes the alternative and its risks.

Raising money. Investors buy shares, and lenders prefer to lend to an entity with a balance sheet of its own. A business that expects to raise capital within the next year should incorporate first, choose a share structure that can accommodate investors and put founder agreements in place while the relationships are good.

A sole proprietorship cannot be sold as a business; only its assets can be sold. A corporation can be sold either way, and the difference matters for tax. An individual who sells qualified small business corporation shares may be able to claim the capital gains deduction, often called the lifetime capital gains exemption, which shelters a substantial amount of the gain from tax. The Canada Revenue Agency's guidance on line 25400 sets out the current limit and the eligibility rules, which in general terms require that the shares be of a Canadian-controlled private corporation, that they have been held for a qualifying period and that the corporation's assets have been used principally in an active business in Canada throughout that period.

Those tests take time to satisfy. A business that incorporates two years before a sale and keeps passive investments out of the operating company is in a very different position from one that incorporates the month before the buyer arrives. Our guide to selling a business describes how buyers approach share and asset purchases. Owners who expect to sell within a decade should treat incorporation as the first step of exit planning and should raise the point with their accountant early.

Incorporating is cheap; running a corporation is not free. Ontario's government fee for online incorporation is $300 as of October 2026, and the initial return and annual return under the Corporations Information Act carry no fee. The real costs are recurring and professional.

A corporation files a T2 corporation income tax return every year, within six months after its year-end, whether or not it owes tax, and the Canada Revenue Agency expects complete financial statements with it. It also files HST returns if registered, runs payroll if the owner draws a salary, keeps separate bank accounts and books, and maintains a minute book with annual resolutions. Legal and accounting fees for a straightforward owner-managed corporation are a predictable annual line; the compliance checklist lists the recurring tasks and our fee estimator gives a sense of the legal component.

Set those costs against the liability protection and the deferral. For a part-time business earning a few thousand dollars a year, the arithmetic rarely favours incorporating. For a business approaching the point where it could not survive a lawsuit, or retaining meaningful profit each year, the costs become the price of a structure the business already needs.

When the tests say it is time, the transition has a legal side and a tax side.

On the legal side, the corporation is a new person. The Canada Revenue Agency's guidance on a change of legal status states that a sole proprietor who incorporates needs a new business number: the corporation receives its own number and corporate tax account, program accounts such as GST/HST and payroll do not transfer automatically and must be opened under the new number, and the old business number and its accounts must be closed. Contracts, leases and licences held in the owner's name must be assigned to the corporation, which frequently requires the landlord's or counterparty's consent. Insurance policies, domain registrations, vendor accounts and bank accounts are moved or reopened. If the business operates under a trade name, the corporation must register that name under the Business Names Act because subsection 2 (1) prohibits a corporation from carrying on business under a name other than its corporate name unless the name is registered by the corporation.

On the tax side, the owner transfers the business's assets to the corporation in exchange for shares. The Income Tax Act contains rollover provisions that can allow that transfer to occur on a tax-deferred basis when a joint election is filed, and the Canada Revenue Agency's guidance notes that an unincorporated business can be converted to a corporation under the transfer-of-property rules. Whether to use them, at what elected amounts and how to value goodwill are questions for an accountant, and the lawyer preparing the transfer agreement should work from the accountant's numbers.

Our guides on whether you need a lawyer to incorporate, registering a corporation in Ontario and what to do in the first 60 days after incorporating cover the mechanics once the decision is made.

1. 1.Could you personally absorb the worst realistic loss the business might cause? If not, incorporate on liability grounds.
2. 2.Does the business earn more each year than you need to draw out? If yes, ask an accountant to model the deferral.
3. 3.Do customers, procurement rules or insurers require a corporation, and if a single client does, does the personal services business rule apply to you?
4. 4.Are you about to hire, take on a partner or raise money? Incorporate before, not after.
5. 5.Do you expect to sell within the next decade? Incorporation starts the clock on share-sale planning.
6. 6.Can the business carry the recurring cost of a second tax return, a minute book and separate books?
7. 7.If you are converting an existing business, plan the asset transfer with an accountant, line up consents to assign contracts and leases, and set up new government accounts before the switch.

Lamba Law's incorporation and structuring practice works with owners and their accountants to time the move, design the share structure and complete the transfer of an existing business into a new corporation. Try our incorporation jurisdiction calculator if you are also weighing Ontario against federal incorporation.