How the Refundable Tax on CCPC Investment Income Works

A Canadian-controlled private corporation pays a deliberately high federal rate on passive investment income — roughly 38⅔% before provincial tax — but about 30⅔% of that amount is refundable. The refundable tax on CCPC investment income sits in a notional account and comes back to the corporation when it pays taxable dividends to shareholders, at a rate of 38⅓% of dividends paid. The design keeps corporate and personal tax roughly aligned so that parking investments inside a company doesn’t produce a large deferral advantage over earning the same income personally.

What Income the Refundable Tax Applies To

The rules target a specific pool called aggregate investment income (AII). Under subsection 129(4) of the Income Tax Act, AII covers net taxable capital gains for the year (after allowable capital losses and any net capital loss carryovers) plus income from property such as interest, rents, and royalties, less property-source losses.¹

Some items sit outside AII. Dividends from other taxable Canadian corporations that are deductible in computing taxable income are handled separately under Part IV. Active business income is excluded entirely because it benefits from the small business deduction. Foreign investment income counts as AII, with adjustments where foreign tax credits have already been claimed.

The capital gains inclusion rate stays at one-half for 2026. The federal government had proposed raising it to two-thirds for corporations, but Prime Minister Carney cancelled that increase in March 2025.² The CRA has confirmed that gains realized before January 1, 2026 remain at the one-half rate.³

How the Federal Rate Stacks to 38⅔%

Three federal layers combine on a CCPC’s investment income. The basic Part I rate is 38%, reduced by the 10% federal abatement to 28%. Section 123.3 then adds a 10⅔% additional refundable tax on AII.⁴ The general tax reduction that lowers the rate for most other corporate income does not apply to a CCPC’s investment income, which is what keeps the total at roughly 38⅔%. Provincial tax lifts the combined rate on passive income to around 50% depending on the province.

The important number sits inside that total. Of the 38⅔% federal tax, approximately 30⅔% of AII feeds a refundable account the corporation recovers by paying dividends. The remaining roughly 8% is the permanent federal cost. The system penalizes accumulating passive income inside the corporation; it does not penalize distributing it.

Part IV Tax on Dividends the Corporation Receives

Portfolio dividends from other Canadian corporations are normally deductible and escape Part I tax. Section 186 fills that gap with a 38⅓% Part IV tax on dividends received from non-connected corporations.⁵ Without it, a CCPC could compound dividend income indefinitely without any tax at the corporate level.

Dividends from connected corporations work differently. A payer is connected to the recipient if the recipient controls the payer (owning more than 50% of the voting shares) or holds more than 10% of both the voting shares and the fair market value of all issued shares.⁶ For a connected-corporation dividend, the recipient’s Part IV tax generally equals the payer’s dividend refund triggered by that dividend. The refundable tax obligation passes up the corporate chain instead of disappearing.

Every dollar of Part IV tax paid is fully refundable. It gets tracked in one of the corporation’s refundable dividend tax on hand accounts and comes back when the corporation pays its own taxable dividends.

The Two RDTOH Accounts: ERDTOH and NERDTOH

Since 2019, refundable tax has been tracked in two separate notional accounts: Eligible Refundable Dividend Tax on Hand (ERDTOH) and Non-Eligible Refundable Dividend Tax on Hand (NERDTOH).⁷ The split prevents corporations from converting passive income taxed at lower rates into eligible dividends carrying higher personal dividend tax credits.

ERDTOH is built from Part IV tax on eligible dividends received from non-connected corporations, plus Part IV tax on dividends from connected corporations to the extent the payer’s own refund came from its ERDTOH. A corporation recovers ERDTOH by paying eligible dividends.

NERDTOH captures the refundable portion of Part I tax on AII, measured at 30⅔% of AII (subject to statutory caps and reductions for foreign tax credits), plus any Part IV tax that doesn’t feed ERDTOH. NERDTOH is recovered by paying non-eligible dividends.

Neither account holds cash. Both are running balances on the corporation’s tax ledger, carried forward and reduced by any refund actually received.

Claiming the Dividend Refund

Section 129 gives a private corporation a refund of 38⅓% of taxable dividends paid, capped at the balance sitting in its RDTOH accounts.¹ A corporation that hasn’t accumulated enough refundable tax doesn’t receive a refund exceeding its balances.

Ordering rules determine which account is drawn down. When non-eligible dividends are paid, NERDTOH is used first; only if the refund claim on those dividends exceeds the NERDTOH balance can the excess come from ERDTOH.⁸ Eligible dividends trigger refunds from ERDTOH only. Getting the sequence wrong can leave a balance stranded in the wrong account or produce a missed refund for the year.

The refund is claimed on the T2 corporate income tax return and is not automatic. The corporation must file within three years of the tax year end and report total taxable dividends paid during that year.¹ Miss the three-year window and the refund for that year is forfeited. Once processed, the CRA issues the refund as a payment or applies it against other amounts owing.

The Small Business Deduction Clawback

Passive income creates a second cost that many owners underestimate. The small business deduction, which gives a CCPC a reduced rate on the first $500,000 of active business income, is clawed back when the corporation or its associated group earns significant passive income. Subsection 125(5.1) reduces the business limit by $5 for every $1 of adjusted aggregate investment income above $50,000 in the previous tax year.⁹

The math is steep. At $50,000 of passive income, the full $500,000 limit is intact. At $100,000, the limit has been cut by $250,000. At $150,000, it hits zero and the SBD is gone entirely. The active income that would have been taxed at the small business rate (roughly 9% federally) instead faces the general corporate rate of around 15% federally, plus provincial tax.

Because the test uses the previous year’s passive income, a one-time capital gain can reduce the SBD for the following year even after passive income drops back down. This clawback is a permanent tax increase on active income, not a refundable one. For CCPCs with both operations and an investment portfolio, the SBD reduction often costs more than the refundable tax itself.

Substantive CCPCs

Restructuring to shed CCPC status no longer sidesteps this regime. For tax years ending on or after April 7, 2022, section 123.3 also applies to “substantive CCPCs” — private corporations that aren’t technically CCPCs but are still controlled, directly or indirectly, by Canadian-resident individuals.⁴¹⁰ An anti-avoidance rule also deems a corporation to be a substantive CCPC where one of the purposes of a transaction was to avoid the section 123.3 tax. Before these rules, some corporations brought in a non-resident or public-company shareholder to break CCPC status and escape both the refundable tax and the SBD clawback. That door is closed.

Where Integration Breaks Down

The theory is that corporate tax plus the shareholder’s personal tax on the dividend should roughly equal the personal tax the shareholder would have paid on the same investment income earned directly. In practice, integration is imperfect. Provincial rates, the gross-up and dividend tax credit, and whether a dividend is eligible or non-eligible all introduce gaps. The total tax through a CCPC can land slightly above or below the personal outcome depending on the province and the shareholder’s marginal rate.

The system works when dividends are paid. It works against the owner when passive income accumulates and dividends don’t. The refundable tax sits in the RDTOH accounts earning nothing, less capital is available to reinvest, and once AAII crosses $50,000 the SBD starts to erode. Between the refundable tax mechanic and the SBD clawback, there is real pressure either to distribute passive earnings on a regular cadence or to reconsider whether investments belong inside the corporation at all.

1
Justice Laws Website. Income Tax Act RSC 1985, c. 1 (5th Supp.) – Section 129
2
Prime Minister of Canada. Prime Minister Mark Carney Cancels Proposed Capital Gains Tax Increase
3
Canada Revenue Agency. What’s New for Small Businesses and Self-Employed
4
Justice Laws Website. Income Tax Act RSC 1985, c. 1 (5th Supp.) – Section 123.3
5
Justice Laws Website. Income Tax Act RSC 1985, c. 1 (5th Supp.) – Section 186
6
Canada Revenue Agency. Part IV Tax on Taxable Dividends Received by a Private Corporation or a Subject Corporation
7
Canada Revenue Agency. T2 Corporation Income Tax Guide Chapter 6 – Refundable Dividend Tax on Hand
8
Canada Revenue Agency. Dividend Refund Rules
9
Justice Laws Website. Income Tax Act RSC 1985, c. 1 (5th Supp.) – Section 125
10
Justice Laws Website. Income Tax Act RSC 1985, c. 1 (5th Supp.) – Section 248