What is a small business deduction and how does it apply to associated corporations?
If you operate a Canadian-Controlled Private Corporation (CCPC) with less than $15 million of taxable capital employed in Canada, you may qualify for the Small Business Deduction (SBD), a powerful tax-saving tool for small business owners.
Under subsection 125(1) of the Income Tax Act (1985), the Small Business Deduction reduces the corporate tax rate on the first $500,000 of active business income. This means your corporation pays a significantly lower income tax rate on eligible income each year.
What Is the Small Business Deduction (SBD)?
The SBD allows qualifying CCPCs to benefit from a 12.2% combined federal and Ontario provincial small business tax rate, compared to the general corporate tax rate of 26.5%.
This reduced tax rate frees up more capital for reinvestment into your business, whether it’s hiring staff, purchasing equipment, expanding operations, or improving cash flow.
The SBD is calculated by multiplying a corporation’s SBD rate by the lesser of:
- Active business income earned in Canada
- Taxable income for the year
- Business limit for the year (maximum $500,000)
Important: Active business income does not include investment, rental, or leasing income.
Limitations for Associated Corporations (Subsection 125(3))
When a corporation is associated with one or more other corporations, the group must share the $500,000 small business limit. This rule prevents business owners from creating multiple corporations solely to access multiple SBD limits.
Associated corporations must file an agreement allocating how the $500,000 business limit will be shared among them when filing corporate taxes.
When Are Two Corporations Considered Associated?
According to Section 256(1) of the Income Tax Act, corporations may be considered associated if any of the following apply:
a. Direct Control
- Corporation A controls Corporation B, or vice-versa.
b. Common Control
- Both corporations are controlled by the same person or group of persons.
Note: Two corporations not directly associated with each other may still be associated through a third corporation.
c. Related Persons With Significant Share Ownership
- Different persons control the corporations,
- Those persons are related, and
- At least one such person owns 25% or more of any class of shares in both corporations.
d. Related Person and Group Control
- A person controls Corporation A,
- That person is related to a group controlling Corporation B, and
- The person owns 25% or more of any class of Corporation B shares.
Explore our Tax Planning for businesses and Business Incorporation services
Definition of Control
Control refers to legal control, generally owning shares carrying more than 50% of the voting rights.
Why Proper Classification Matters
Being incorrectly categorized as associated or missing a required association filing can lead to:
- Loss of SBD eligibility
- Interest and penalties
- CRA reassessments
- Unexpected tax liabilities
A corporate tax lawyer can help you determine your structure, eliminate risks, and maximize tax savings.
Are you unsure whether your corporations are associated, or do you want to confirm your eligibility for the Small Business Deduction?
Our experienced business and tax lawyers at Kalfa Law Firm can help you properly structure your corporation and maximize the benefits available to you under the Income Tax Act.
Contact Kalfa Law Firm today to speak with a business lawyer about your SBD eligibility and corporate tax planning needs.
FAQs:
-Youstina Tawadrous, Corporate-Commercial Law Clerk
Youstina is a corporate-commercial law clerk at Kalfa Law Firm as well as a Law Society of Ontario Lawyer Licensing Candidate. Tina graduated in 2020 with an LL.B in Laws from the University of Leicester after completing a BSc. at Dalhousie University.
© Kalfa Law Firm 2025, updated April 2026
The above provides information of a general nature only. This does not constitute legal advice. All transactions or circumstances vary, and specified legal advice is required to meet your particular needs. If you have a legal question you should consult with a lawyer.
