Introduction

For most physicians in Canada, the annual premium paid to the Canadian Medical Protective Association (CMPA) is one of their largest professional expenses — and one of the most straightforward from a tax standpoint. Yet questions about whether CMPA premiums are deductible, how they are deducted, and whether the deduction changes when a physician is incorporated come up regularly.

This article clarifies the tax treatment of CMPA premiums under current CRA rules.

What Is the CMPA Premium?

The Canadian Medical Protective Association (CMPA) is a not-for-profit mutual defence organisation that provides medical liability protection to physician members. Annual membership fees — commonly referred to as CMPA premiums — vary by specialty and practice setting, and can range from a few thousand dollars for certain lower-risk specialties to over $50,000 annually for high-risk surgical and obstetric specialists.

These premiums represent the cost of professional liability protection and are directly connected to the practice of medicine.

Deductibility for Unincorporated Physicians

A physician practising as a self-employed individual (unincorporated) reports professional income on Form T2125 of their T1 personal return. CMPA premiums paid in the year are deductible as a professional expense on that form, provided they relate to the professional practice that generates income.

The deduction reduces net professional income, which in turn reduces federal and provincial personal tax. CPP contributions on self-employment income are calculated on net self-employment income, so the CMPA deduction also reduces CPP obligations where applicable.

Deductibility for Incorporated Physicians

When a physician operates through a medical professional corporation (MPC) and pays CMPA premiums through the corporation, the premium is deductible as a business expense of the corporation — provided it is a genuine operating expense incurred for the purpose of earning professional income.

This means the CMPA premium reduces the corporation's net income before the corporate tax rate is applied. At the small business rate (approximately 12.2% combined in Ontario in 2026), the after-tax cost of the premium is lower when paid through the corporation than when paid personally at marginal rates that can exceed 53%.

This is one of the tangible cost advantages of operating through a professional corporation for high-premium specialties.

The Provincial Government Rebate Programs

Several provincial governments — including Ontario — have historically provided rebate programs that partially offset CMPA premiums for physicians practising in the province. In Ontario, the CMPA Grace Period and the provincial rebate arrangement have evolved over time. The taxability of any rebates received depends on the nature of the payment and whether it was received personally or through the corporation.

Rebates received by the corporation that relate to previously deducted CMPA expenses are generally included in corporate income. Rebates received personally may be income in the year received. The treatment should be confirmed with a CPA in the year the rebate is received, as the structure of provincial rebate programs can change.

What If the Premium Covers Both Personal and Corporate Periods?

In a year when a physician incorporates mid-year, the CMPA premium may straddle a period of personal practice and a period of corporate practice. The portion of the premium attributable to the corporate period is deductible by the corporation; the portion attributable to the personal period is deductible on the T1. Proper allocation between the two is necessary where the premium was paid as a single annual amount.

Documentation

The CRA expects that business expenses claimed by a corporation be supported by documentation. CMPA invoices or annual statements are the appropriate support for this deduction. These should be retained as part of the corporation's books and records.

When to Speak With a CPA

For most physicians, the CMPA deduction is straightforward — but the interaction with provincial rebates, the allocation between personal and corporate periods, and the timing of payments can create complexity in transitional years. A CPA familiar with medical professional corporations can ensure the deduction is claimed correctly in each year.

Rotaru CPA works with physicians and medical professionals across Ontario on professional corporation tax compliance. Book a consultation to discuss your practice.