Corporate Tax Leak Calculator for Canadian CCPCs | Dundas
Free Tool for Incorporated Business Owners

The Corporate Tax Leak Calculator

Three ways money leaks out of a Canadian corporation — while you build it, when you pay yourself, and when you die. Run your own numbers. Honest Ontario math, every assumption editable, nothing inflated.

Tell me about your corporation
Active business income before owner salary or dividends.
What's built up inside the corporation after tax.
Corporate money with no job — savings, GICs, a lazy investment account.
Each type of investment income is taxed differently inside a corporation.
Problem 1 — While you're building
What your idle money costs in corporate tax this year
$0
Where every dollar of corporate tax goes this year
Base tax
Idle cash tax, gone for good
Idle cash tax, refundable later
Base corporate tax
$0
Cost of doing business on your active income.
Unavoidable
Idle cash tax drag
$0
This year's tax on the growth of money with no job.
Restructurable
How we calculated this
Problem 2 — When you take money out
Tax on your next $100,000 of salary once you're already in the top bracket
$0
Not all extraction methods cost the same — personal tax per $100k
T4 salary
Non-eligible dividends — profits taxed at the small business rate
Eligible dividends — profits taxed at the general rate
How we calculated this

Each bar is the personal tax on $100,000 taken out at the top Ontario bracket (income above roughly $258,000 in 2026), using the rates in the assumptions panel below.

The dividend rate depends on how the profit was taxed inside the corporation. Profit taxed at the small business rate comes out as non-eligible dividends (47.74% top rate in 2026, rising to 48.89% on January 1, 2027). Profit taxed at the general corporate rate builds GRIP (the general rate income pool) and comes out as eligible dividends (39.34% top rate). Below the top bracket, every rate is lower.

Problem 3 — When you die
Two ways the money can come out — the estate pays one, not both
Wind-up route — heirs extract retained earnings as dividends (the unplanned default)
Capital gains route — deemed disposition of shares (ITA s.70(5)), preserved via pipeline planning
Going to CRA
$0
On the unplanned wind-up route
What your family actually receives
$0
After CRA's bill is paid
How we calculated this

We assume the shares are worth about the retained earnings and were bought for next to nothing, with no growth and today's rates.

Wind-up route (headline): the retained earnings come out to the heirs as non-eligible dividends at the top rate. Capital gains route: the deemed sale of the shares at death (ITA s.70(5)) is taxed as a capital gain, only half of which is taxable, and pipeline planning keeps that treatment.

A properly administered estate pays one of these, not both. Post-mortem strategies (pipeline planning, the s.164(6) loss carryback) decide which, and corporate-owned life insurance with the capital dividend account reduces the bill further. The unplanned number is the point of the conversation, not a prediction.

Edit tax rate assumptions
Ontario combined small business rate (11.2% from July 1, 2026; was 12.2%)
Ontario combined general rate
Ontario rate on interest and the taxable half of capital gains
Part of the passive rate refunded when the corporation pays taxable dividends (NERDTOH)
Tax on Canadian public-company dividends received. Fully refundable (ERDTOH)
Ontario top combined marginal rate
Top rate on income that was taxed at the small business rate
Top rate on income that was taxed at the general rate (GRIP)
Currently 50% — only the taxable half counts
Max active income eligible for the small business rate
Assumed annual return on idle money (interest, dividends or realized gains)
Extra tax on active income that loses the small business rate. In Ontario only the federal rate changes (9% → 15%) because the province keeps its own small business rate. Alberta and BC also lose theirs.

Every one of these leaks has a fix.

None of the numbers above are a prediction — they're what happens by default when nobody plans. Here's the shape of the fix for each one:

Fix for Problem 1

Give idle cash a job

Corporate dollars redirected into an insurance-sheltered structure grow without generating annually taxed passive income — no yearly tax drag on that growth.

Fix for Problem 2

Sequence how money comes out

Not every dollar has to leave as salary or dividends. A long-term plan decides what you take, when, and in what form — and leaves the rest compounding inside the structure.

Fix for Problem 3

Turn the estate bill around

Corporate-owned life insurance proceeds credit the capital dividend account — so money can flow to your estate as tax-free capital dividends instead of the taxed default.

The three questions owners usually ask next

Fair question #1

“Should my accountant see this?”

Yes — and we mean it. Bring them to the conversation, or we'll walk them through the numbers directly in a 15-minute call. The plan only works if the person who files your return is on side.

Fair question #2

“Is this just a way to sell me insurance?”

The strategies often use corporately-owned life insurance as the chassis — that's where the tax treatment comes from. We're straight about exactly what it is, what it costs, and the trade-offs before you're asked to decide anything.

Fair question #3

“What's the catch?”

There are real trade-offs: these are long-term structures, early-year cash values can sit below what's been paid in, and carrier dividend scales can change. You'll see all of it in writing — we show the downsides unprompted.

The Corporate Wealth Shield™ is our framework for putting these in place — in the right order, coordinated with your accountant. Bring these numbers to a free Gap Analysis and we'll show you which leaks apply to your structure.

Book Your Free Gap Analysis

15 minutes. No obligation. You keep the analysis either way.

Understand what's behind these numbers: Passive income and the small business deduction · Corporate-owned life insurance

For discussion purposes only. All figures are illustrative estimates based on the rates in the assumptions panel (Ontario defaults, 2026) and are not tax, legal, or financial advice. Actual liability depends on your corporate structure, adjusted cost base, RDTOH and GRIP balances, shareholder agreements, and individual circumstances. Open “How we calculated this” under any number to see the method, and review every strategy with your accountant and lawyer before acting.