Key Takeaways
- Above $50,000 of passive income, a CCPC loses $5 of small business limit for every extra $1 — the limit is gone at $150,000.
- Investment income is taxed at 38⅔% federally, but 30⅔% is refundable — recovered only when the corporation pays taxable dividends.
- Capital dividends pay out tax-free but trigger no dividend refund; only taxable dividends unlock the refundable tax.
Your Corporation Starts Investing. Then Ottawa Starts Taking a Bigger Bite Out of Your Business.
Imagine your business has a great year. You pay yourself what you need, cover payroll and expenses, and leave the rest in the company. Instead of letting that money sit idle, you invest it.
It seems like the sensible, responsible move. Then Ottawa steps in, and suddenly you need to understand the grind, the refund, and — worst of all — the traps that could squeeze the very business that makes the money in the first place.
During the process, you don't have to become an accountant. You just have to see how the rules work.
Layer One: Your Investment Portfolio Can Shrink Your Small-Business Tax Break
A Canadian-controlled private corporation's first $500,000 of active business income is taxed at Canada's small-business rate. Since 2019, adjusted aggregate investment income, or AAII — roughly your business's eligible taxable capital gains (excluding gains on assets used in the business) and property income, with dividends from connected corporations deducted — reduces that limit.
Here's how the grind works: For every $1 of AAII above $50,000, your corporate small-business limit is reduced by $5. At $50,000 of AAII, the passive-income reduction has not started. At $100,000, half of your small-business limit is gone. At $150,000, the entire $500,000 limit is gone.
Two details make the grind sting. It includes the AAII of your corporation and its associated corporations. And it uses the AAII from tax years ended in the preceding calendar year, so your investments' success this year can raise the tax bill on your business next year. That fact is important, because your investments may underperform the following year, and the grind does not forgive you.
Layer Two: The 38⅔% Investment Tax That Isn't Entirely Gone Forever
Federally, when your Canadian-controlled private corporation earns investment income, that income is taxed at 38⅔%. That tax consists of an unreduced 28% general rate plus a 10⅔% additional tax. Of that, 30⅔% is refundable and accumulates in your refundable dividend tax on hand accounts.
It comes back only when you pay corporate shareholders taxable dividends, and the refund is calculated at 38⅓% of the taxable dividends paid — about $38.33 for every $100 of taxable dividends — subject to the amount available in the account.
Since 2019, the refundable tax is split into two accounts.
- ERDTOH — eligible refundable dividend tax on hand — is fed mainly by refundable tax associated with eligible-dividend flows. Eligible dividends can only get that refund from ERDTOH.
- NERDTOH — non-eligible refundable dividend tax on hand — holds refundable Part I tax on investment income, along with applicable Part IV tax. Non-eligible dividends take their refund from NERDTOH first, and once that balance is exhausted, eligible refundable tax on hand can also become available for a refund through non-eligible dividends, subject to the rules.
There's a third tax you'll need to understand: Part IV tax of 38⅓%. It applies to portfolio dividends your corporation receives from non-connected corporations, and it is also refundable through the same dividend-refund mechanism.
The Traps: Where Corporate Investment Strategies Get Complicated
1. Your Refund Is Hostage to the Dividend
The refundable tax isn't a rebate the Canada Revenue Agency sends you. It is recovered only when the corporation pays taxable dividends to shareholders. That means you often need to incur personal tax to recover corporate tax. Money left invested keeps its refund locked in the account.
The elegant trap? Paying a capital dividend — the tax-free kind, paid from the capital dividend account — earns no dividend refund at all. A companion Twikup guide, The Capital Dividend Account, Explained, covers how that account fills and pays out.
2. The Exceptions Can Be Real, Even If They Are Narrow
Dividends from connected corporations — corporations you control, or that you hold more than 10% of in votes and value — do not count toward AAII and generally escape Part IV tax, unless the dividend earned its payer a refund.
At the other edge, income a Canadian-controlled private corporation earns by providing services or property to a related private corporation — called "specified corporate income" — generally loses the small-business deduction unless nearly all its active income comes from arm's-length sources or the payer assigns it part of its own business limit.
And a "specified investment business" can still earn small-business-deduction-eligible active income if it employs more than five full-time employees.
One More Thing: The Federal Tax Bill Isn't the Whole Bill
Every rate discussed in this guide is federal. Provinces also tax a corporation's investment income, and their share is not refundable. So the actual upfront cost of corporate passive income is higher than the federal numbers alone suggest.
The Twikup Take
Corporate investing isn't a bad strategy, it is simply more rationed than many people realize. Below $50,000 of passive income, the passive-income reduction on the small-business limit has not kicked in. However, the corporate investment tax and refundable-tax rules still apply.
Above that amount, every additional dollar of passive income can reduce the small-business limit by $5, progressively forcing more business income into the higher general corporate rate. And the tax you pay upfront sits locked in a refundable-tax account until you pay taxable dividends, making your personal tax planning part of the strategy whether you like it or not.
The real surprise isn't that Ottawa taxes corporate investments. It's that your investment portfolio can eventually make running your actual business more expensive.
Image: Illustrative image.