By Shea Sanche, CFP® · Last reviewed: October 2026
Retained earnings are the profits your corporation has kept after tax. When the business does not need all of that money, the corporation can invest it. A corporation can hold an investment account in its own name. You do not need a holding company to do it.
The question is how. A corporation is taxed differently from you, so a portfolio that suits a personal account may not suit a corporate one. This article is educational. Your accountant confirms your corporation's figures.
Decide what the money is for
Before choosing investments, sort the money by its job.
- Operating cash. What the business needs to run and to pay its tax.
- A reserve. Money set aside for a slow stretch, equipment or an opportunity.
- Long-term surplus. Money the business is unlikely to need for years.
Only the third group belongs in a long-term portfolio. The first two need to stay stable and easy to reach.
How each kind of return is taxed
Inside a corporation, the kind of return matters as much as the amount.
| Kind of return | Tax in the corporation | Toward the $50,000 line |
|---|---|---|
| Interest | Fully taxable, at high rates | Counts in full |
| Most foreign income | Fully taxable, at high rates | Counts in full |
| Realized capital gain | Half is taxable. The inclusion rate is 50% | The taxable half counts, in the year it is realized |
| Growth not yet realized | Not taxed until the gain is realized | Does not count yet |
Dividends from Canadian companies follow their own rules, which your accountant can explain.
Two tax accounts sit behind the portfolio.
- The capital dividend account. The non-taxable half of a capital gain is added to it. A capital dividend paid from that balance is received tax-free by Canadian-resident shareholders. See The Capital Dividend Account, Explained.
- Refundable tax. Part of the tax a corporation pays on investment income is refundable when it pays taxable dividends. It is tracked as refundable dividend tax on hand, or RDTOH.
The $50,000 line
Investment income can also change the tax on the business. A Canadian-controlled private corporation gets the federal small business rate on up to $500,000 of active business income. When the corporation and its associated corporations together earn more than $50,000 of passive investment income in a year, that limit is reduced by $5 for every $1 over $50,000. At $150,000 it is gone.
The full rule is in The Passive Income Rule for Canadian Corporations.
A worked example, in dollars
Two corporations each have $500,000 or more of active business income. Each earns $80,000 from its investments in a year, in different ways.
| Corporation A | Corporation B | |
|---|---|---|
| What the portfolio produced | $80,000 of interest and foreign income | An $80,000 realized capital gain |
| Counts toward the line | $80,000 | $40,000 |
| Over the $50,000 line | $30,000 | $0 |
| Federal business limit removed | $150,000 | $0 |
| More federal tax on business income, before provincial tax | $9,000 a year | $0 |
| Added to the capital dividend account | $0 | $40,000 |
For Corporation A, the federal rate on the $150,000 of business income that loses the limit is 15%, not 9%. That difference is the $9,000.
Both corporations still pay tax on the investment income itself. The table shows only what happens to the business limit and the capital dividend account. The two portfolios are not the same investments and do not carry the same risk. The point is narrower: the kind of return changes the tax result. This is an illustration, not your corporation's figures.
What a low-distribution portfolio does
A low-distribution portfolio is built to pay out less along the way, so less investment income lands on the corporation's return each year. Growth that stays in the portfolio is not on the return until a gain is realized. When it is realized, half is taxable and the other half is added to the capital dividend account.
It does not remove tax. The taxable half of a realized gain still counts as investment income in the year it is realized, so the timing of gains is part of the plan.
Tax is one input, not the only one. How long the money can stay invested, the risk the business already carries and your need for cash all matter.
If you may sell the company one day, raise it with your accountant early. A corporation that holds too much in passive assets can put the lifetime capital gains exemption at risk on a share sale.
What your accountant does, and what we do
Your accountant is in charge of the corporation's tax. They know what the corporation earned, how you are paid and what its tax accounts hold. They prepare the year-end, file the return and decide with you when dividends are paid.
Our part is the investment account: what the corporation owns, what it pays out and when gains are realized. We build corporate portfolios to be low-distribution, so passive income is planned for, not discovered at filing. With your permission, we coordinate directly with your accountant. Nothing is ever paid between us and your accountant, in either direction.
Common Questions
Short answers to the questions owners ask.
How should I invest retained earnings in my corporation?
Do I need a holding company to invest corporate money?
Is interest taxed differently from capital gains in a corporation?
Should I take the money out and invest it personally instead?
Is there a minimum to open a corporate investment account with Insight Planning?
Related Reading
- The Passive Income Rule for Canadian Corporations
- Investing Through a Holding Company in Canada
- The Capital Dividend Account, Explained
- Salary vs Dividends for Business Owners
- Should You Set Up a Holding Company in Canada?
Key Takeaway
Investing retained earnings well starts with the tax rules, not the investments. Interest and most foreign income are taxed at high rates and count in full toward the $50,000 line. Half of a realized capital gain is taxable, and the other half is added to the capital dividend account. Set the plan with your accountant before the money is invested.
Start with the number
The Corporate Tax Efficiency Test is by request, and free for owners who qualify. It names the problem in dollars. To see how we invest corporate money, read Insight Corporate Wealth.
Request an IntroductionWe work with owners from British Columbia to Ontario. Our minimum for new client relationships is $1,000,000.
This article is general education for Canadian business owners. It is not tax, legal or investment advice, and it does not replace your accountant. The tax figures are federal and were checked against Canada.ca on October 7, 2026. Tax rules change, and the provincial effect depends on your province. All investments involve risk, including the possible loss of principal. Your accountant confirms your corporation's figures.