The Lifetime Capital Gains Exemption for Ontario Dentists: Who Qualifies and What It Is Worth

For many dentists, selling the practice produces the largest capital gain of their lives. The lifetime capital gains exemption can shelter up to $1,275,000 of that gain in 2026. For someone who has not used any of it, that is worth up to about $341,000 of regular tax at the top Ontario rate, before the minimum tax. But it applies only to a sale of shares by someone resident in Canada, only if the shares pass three tests, and a large claim can bring in the alternative minimum tax in the year of the sale.

This post covers who qualifies, what can disqualify a dental corporation, how the exemption can be used in pieces, and how the minimum tax applies to a large claim. It is written for dentists selling shares of an Ontario dentistry professional corporation. It is orientation, not tax advice: your accountant confirms whether your shares qualify and how much you can claim.

If you are a physician: the same law applies to a medicine professional corporation, but many physician practices have little saleable goodwill, so a qualifying share sale is less common. The physician section of the guide to selling or closing a practice corporation covers what usually matters more.

What the exemption is worth

The exemption is a lifetime limit on the capital gains an individual can shelter from tax on qualifying shares. For dispositions in 2026 the limit is $1,275,000, according to the CRA's indexation table. It is indexed to inflation each year, so if you are selling in 2027, check the CRA's table for that year's figure.

Three things decide what it is worth to you:

• Only a sale of shares qualifies, and only an individual claims it. If your corporation sells the practice's assets instead, the corporation is the seller and the exemption does not apply. A capital gain on the sale, such as on goodwill you built, is taxed inside the corporation, as capital gains inside a CCPC explains, and the non-taxable half of its net capital gains can be added to its capital dividend account. An asset sale can also produce recapture of depreciation claimed on equipment or purchased goodwill, and other business income, which are taxed as income and do not get that treatment. The exit guide compares the two kinds of sale.
• It is a lifetime total. Anything you have claimed before, for example on an earlier sale, reduces what is left.
• The value depends on your tax rate. As a top-rate illustration, at the 2026 top Ontario rate on capital gains of 26.76 percent, a full claim of $1,275,000 is worth up to about $341,000 of regular tax ($1,275,000 × 26.76% = $341,190). That is before the alternative minimum tax, covered below, which a large claim can trigger in the year of the sale.

Family members who own shares have their own exemption. In Ontario, non-voting shares of a dentistry professional corporation can be owned by a spouse, child or parent of a voting shareholder, as the professional corporation guide explains. On a share sale, each owner can claim the exemption on their own gain if the shares pass the same tests. Passing the tests does not settle whose gain it is. Your accountant must also confirm that attribution rules do not assign the gain to someone else: a gain on shares you gave or transferred to your spouse, for example, can be taxed in your hands. A taxable capital gain on qualifying shares is generally excluded from the tax on split income, though a minor child's gain can be treated differently. What a dental corporation cannot use is the approach common for other businesses of multiplying the exemption through a standard family trust, because a trust whose beneficiaries include anyone outside a narrow permitted class, such as a spouse, an adult child or a company, cannot own the shares. The one trust Ontario allows is individuals holding non-voting shares as trustees for a voting dentist's minor children, as the post on family trusts and professional corporation shares explains.

Who qualifies

The exemption is for individuals resident in Canada throughout the year of the sale. You are also treated as resident throughout the year if you were resident at some point in it and throughout the year before or the year after, so a move into or out of Canada around a sale needs your accountant's attention early.

Beyond residency, your shares qualify only if the corporation is a Canadian-controlled private corporation and the shares pass three tests:

1. At the time of sale, all or substantially all of the fair market value of the corporation's assets must be used mainly in a business it actively carries on in Canada. The Income Tax Act does not put a number on "all or substantially all". The CRA's capital gains guide reads it as 90 percent or more, which is why 90 percent is the figure you will hear.
2. Throughout the 24 months before the sale, no one other than you or a person related to you can have owned the shares.
3. Throughout those 24 months, more than 50 percent of the fair market value of the corporation's assets must have been used in the active business.

Two points about these tests are easy to miss.

The tests use fair market value, not the balance sheet. The largest active asset of most dental practices is goodwill, and goodwill you built yourself does not appear on the corporation's balance sheet at all. As an illustration, suppose the practice's goodwill, equipment and working capital are worth $1,800,000. At the sale, the corporation could hold up to about $200,000 of investments and still meet the 90 percent reading, because $200,000 is 10 percent of the $2,000,000 total. Throughout the 24 months before, its investments would have to stay below the value of its active assets. The goodwill figure is a valuation, so the margin is only as reliable as the valuation behind it.

New shares start a new clock. Shares a corporation issues are generally treated as having been owned by an unrelated person immediately before they were issued, so shares issued less than 24 months before a sale generally fail the holding test. The exceptions are shares issued in exchange for other shares, shares issued when all or substantially all the assets of an active business were transferred to the corporation, and shares issued as a stock dividend. This matters if new shares went to you or a family member shortly before a sale.

What can disqualify a dental corporation

Passive assets count against you in both asset tests, and a dental corporation tends to build them up. In Ontario a holding company cannot own shares of a dentistry professional corporation, as the post on holding companies and professional corporations explains, so savings stay in the company you would sell. The usual causes:

• An investment portfolio built from retained earnings. How it is taxed while it is there is covered in the corporate investing guide.
• Cash beyond what the practice needs. Cash needed to run the practice is generally treated as an active asset; a surplus balance is not.
• The cash value of a permanent life insurance policy. Where the corporation owns a policy on the life of a shareholder of the corporation, or of a connected corporation, the tax rules value the policy at its cash surrender value for these tests, and that value is not an active asset. A large whole life or universal life policy can tip the tests, while a term policy generally has no cash value to count. The corporate-owned life insurance guide covers when a policy belongs in the corporation at all.
• Property held to earn rent from others. Premises the practice itself uses are generally an active asset.

Disclosure: I am a licensed insurance and investment advisor and life insurance is among the products I place, so have your lawyer and accountant review any structure, including one I suggest.

Fixing a corporation that fails. Removing passive assets before a sale is called purification. Other business owners usually do it by paying the surplus to a holding company as a generally tax-free intercorporate dividend. A dental corporation cannot, so the routes that remain, such as paying the surplus out as personally taxed dividends over several years or using it in the practice, cost more and take longer. If the corporation has failed the 24-month test, restoring eligibility may require a fresh 24-month period. The exit guide sets out the trade-off, and your accountant should model it before anything moves.

Using the exemption in pieces

The exemption does not have to be used in one sale. It is a lifetime total, and any part you do not use stays available for a later qualifying disposition.

• A sale in stages. If an associate buys into the practice by purchasing some of your shares now and the rest later, each sale can use part of your exemption. Each sale is tested on its own date, so the corporation has to pass the tests each time, and each buyer must be an eligible purchaser under Ontario's ownership rules.
• Shares you still own at death. At death your shares are generally treated as sold at fair market value. If they pass to your spouse, the spousal rollover rules can instead defer the gain until your spouse disposes of them or dies. Where a gain does arise and the shares qualify, any exemption you have left can shelter it. The minimum tax described below does not apply in the year of death.
• Not on shares your corporation buys back. When a corporation redeems or buys back its own shares, what it pays above their paid-up capital is generally taxed as a dividend, not as a capital gain, so the exemption does not shelter it.
• A cumulative net investment loss can limit a claim. If, since 1988, your investment expenses, such as interest on money borrowed to invest, have exceeded your investment income, that excess reduces what you can claim in the year of the sale. Certain business investment losses you have deducted reduce it too. Your accountant can check this well before a sale.

The alternative minimum tax

The alternative minimum tax is a parallel calculation that makes people with large deductions pay some tax. It is not specific to the exemption: other large capital gains and deductions can trigger it too. Since 2024, the whole capital gain counts in that calculation and the exemption removes only 70 percent of it, so 30 percent of a sheltered gain is exposed. If the minimum tax is higher than your regular tax for the year, you pay the difference.

Here is the 2026 figure for an Ontario dentist who sells qualifying shares at a capital gain of exactly $1,275,000, has not used any of the exemption before, claims all of it, and has no other income that year. Their regular tax is nil, because the exemption shelters the whole gain.

On these assumptions, that is the tax payable in the year of the sale. Some or all may be recovered, depending on your tax position over the following seven years.

How recovery works. Federal minimum tax can be carried forward for seven years and deducted in any of those years to the extent your regular tax is higher than your minimum tax, and Ontario has a matching credit. Whether you recover all of it depends on how much regular tax you pay in those years, which for a retired dentist depends on how the corporation, any pension and your RRSP pay you.

Other income changes the number. With salary, dividends or other income in the year of sale, the figure can be higher or lower than this example, so your accountant should run it on your actual numbers.

Questions for your accountant

1. How much of my exemption is left, and do I have a cumulative net investment loss?
2. Using a current valuation of the practice, do my corporation's shares pass the three tests today?
3. Which assets in the corporation count as passive, including the cash value of any life insurance policy?
4. Do family members own shares that could claim their own exemption, and were any shares issued in the last 24 months?
5. If I claim the exemption, how much minimum tax would I pay in the year of sale, and how quickly would I recover it?

The financial planning for dentists and financial planning for physicians pages explain how I work with each profession on what the corporation holds before a sale and how it pays you after one.

I am a licensed insurance and investment advisor, not an accountant or a lawyer. Whether your shares qualify, and how much you can claim, is your accountant's call, and how a sale is structured is your lawyer's. This post is orientation, so that you can ask those questions early enough for the answers to matter.