Incorporating your dental practice: what a DPC actually buys you

When a DPC starts paying for itself

Incorporation pays once you reliably earn more than you spend. Profit retained in a Dentistry Professional Corporation is taxed at about 12.2% under Ontario's small business rate, while the same dollar on your personal return can face a marginal rate of 53.53%. That spread — roughly 41 cents on the dollar — becomes capital for the next operatory, a CEREC unit, or the loan payments on the practice you just bought.

The buy-in is where the math gets loud. Most dentists purchase a practice with bank debt, and loan principal is repaid from after-tax dollars. Clearing a seven-figure acquisition loan with corporate dollars taxed at 12.2% instead of personal dollars taxed at half shortens the amortization schedule by years.

Two honest caveats. An associate with student debt and nothing left over gains little beyond compliance costs. And a DPC does not shield you from malpractice — professional liability follows the dentist personally, which is why RCDSO Professional Liability Program coverage still does the clinical heavy lifting. The corporate wall helps with leases, equipment financing, and trade creditors, not patient claims.

RCDSO rules: the name, the shares, the certificate

A DPC is an Ontario (OBCA) corporation holding a Certificate of Authorization from the Royal College of Dental Surgeons of Ontario — federal incorporation is not an option, and neither is a numbered company. The name follows the College's pattern, built around a dentist shareholder's surname and ending in Dentistry Professional Corporation, and the articles must restrict the business to practising dentistry and related activities. Investing surplus funds is permitted, which is how mature DPCs end up holding portfolios.

Share ownership is where dentists get a break most regulated professions don't:

Renew the Certificate of Authorization on the College's schedule and report share changes promptly — issuing shares to anyone outside the permitted list puts your authorization to practise through the corporation at risk.

Hygiene corps and holdcos: what still works

The classic hygiene-corporation playbook is mostly closed. Before 2016, a spouse-owned service company billing the practice for hygiene services could claim its own small business deduction and pay the spouse dividends. The specified corporate income rules now force a service company earning its income from a related practice to share the practice's $500,000 limit, and the 2018 tax on split income (TOSI) rules tax most dividends to family who don't actively work in the business at top rates. If someone pitches you this structure at a study club, ask which of those two rules they think doesn't apply.

A holding company cannot own DPC shares — every shareholder must be on the permitted list. What still works: a separate, ordinary corporation owned by you or your family can hold the clinic real estate and lease it to the DPC at market rent, keeping the building out of any future practice sale. The DPC itself can also invest retained profit, though US securities inside the corporation bring T1135 reporting and other questions we cover on our cross-border tax page for dentists.

Family shares and the eventual practice sale

Non-voting family shares earn their keep at the sale, not before. Dividends sprinkled to a spouse or adult children generally trip TOSI while you're practising. But when DPC shares that count as qualified small business corporation shares are sold, each shareholder — family included — can claim their own lifetime capital gains exemption, now $1.25 million, and TOSI generally does not apply to those qualifying gains. A family of shareholders can shelter multiples of what a solo shareholder can.

That outcome takes housekeeping: a minute book that actually reflects who owns what, and a corporation kept clean enough — active practice assets, not an oversized investment portfolio — to pass the qualification tests in the period before closing. Consolidator due-diligence teams read share ledgers closely. We keep DPC records sale-ready as part of ongoing incorporation and compliance work.

CRA program accounts for a new DPC

The corporation gets its own business number and starts from zero with the CRA. Most dental practices need two program accounts, not four:

• RC — corporate tax. A T2 return is due every year from incorporation, including the short first year.
• RP — payroll. Hygienists, assistants, and admin staff move onto the DPC's payroll with T4s and remittances under the new number — our dental payroll page covers the cutover.
• RT — GST/HST, usually not needed. Most dental services are HST-exempt, so most DPCs never register. A purely cosmetic revenue stream — whitening or veneers with no clinical purpose — is taxable, and once taxable revenue passes $30,000 in four rolling quarters, registration stops being optional.

Source: Royal College of Dental Surgeons of Ontario.