After-tax IRR is calculated via XIRR — a date-aware formula that handles irregular cash flows and compounds returns continuously, not annually.
Taxes on corporate investment income are paid from the operating account, not the investment account — so they don't reduce the portfolio balance but they do reduce the true return.
For periods under 10 years, IRR may not represent long-term expected performance; 10-year windows smooth out market cycles.
Use taxes actually paid (from T2 line 710 and provincial equivalent), not net-of-RDTOH amounts — the cash that left the corporation is what compounds elsewhere.
Liquidation tax on unrealized gains must be subtracted to calculate the net after-tax return if the portfolio were sold today.
Tax topic – Talk to your CPARelated to Mutual Funds
Disclosure. I am a licensed Financial Security Advisor, Mutual Fund Representative, and Group Insurance & Annuity Plans Advisor. I am not a lawyer, tax lawyer, or accountant. I discuss taxes only as they relate to specific insurance, investment, and estate strategies; I do not provide general tax optimization or comprehensive wealth strategy services. Content is educational only. Mutual funds offered through WhiteHaven Securities Inc. Insurance products offered through iAssure Inc. Coordinate decisions with your CPA, notary, or lawyer. See Disclaimer and Privacy.
Calculator
Corporate Investment Account IRR Calculator
Calculate your true after-tax IRR. See how taxes affect your returns and get a 20-year projection.
Most business owners see account growth but don't know their true after-tax IRR. Taxes paid from your operating account reduce your real return but aren't visible in the investment account balance. This calculator shows your actual performance after accounting for all taxes paid on investment income.
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Account Information
About your calculation period: For meaningful long-term analysis, periods of 10 years or more are most representative. Shorter periods (2-5 years) may not reflect your long-term expected returns, especially given recent market performance.
The account balance at the start of your evaluation period. This should be the balance as of the start date you select below.
The month and year when your evaluation period begins. This should match when your starting balance was recorded.
Format: MM-YYYY (e.g., 01-2020). You can also type month names like "Jan 2020" and it will be converted automatically.
The current account balance (or balance at the end of your evaluation period). This is the balance before accounting for taxes paid.
The month and year when your evaluation period ends (typically today's date for current analysis).
Format: MM-YYYY (e.g., 01-2020). You can also type month names like "Jan 2020" and it will be converted automatically.
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Cash Flows
Recurring Monthly Transactions
Add regular monthly deposits or withdrawals that occurred over a period
One-Time Transactions
Add individual deposits or withdrawals at specific dates
3
Taxes Paid on Investment Income
Where to Find This Information
Find the total taxes paid on investment income (capital gains tax, dividend tax, interest tax) on your Federal (T2) and Provincial corporate tax returns for each tax year in your evaluation period. This is the tax paid on investment income, not from the investment account itself, but from your operating account at tax time.
Note: If you don't have this information, you can skip this step and see your pre-tax IRR. However, the after-tax IRR will be more accurate for understanding your true performance.
About RDTOH: Use actual tax paid (not net after RDTOH), as this reflects the cash that left your account and isn't compounding. RDTOH refunds are future cash inflows when dividends are paid. Learn where to find these amounts on your T2 return.
4
Calculate Liquidation Tax
Input your current positions to calculate capital gains tax if you were to liquidate today. This helps show your net after-tax return if you sold all holdings.
Security
Shares/Units
Avg Cost ($)
Current Price ($)
Unrealized Gain
Actions
Verification:
This calculator is illustrative only and not a substitute for professional advice.
Assumptions: Uses your inputs (balances, dates, cash flows, taxes paid). IRR calculated via standard XIRR methodology. Tax rates and rules vary by province and year. Consult your CPA before making decisions.
Tax Optimization Strategies
Favor Capital Gains Over Interest
Capital gains are taxed at approximately 25% at the corporate level (50% inclusion rate × 50% corporate rate), while interest income is taxed at ~50%. Over time, this difference compounds significantly. Consider [corporate-class funds](/learn/corporate-class-funds/) that convert interest and dividends to capital gains.
Manage the $50,000 Passive Income Threshold
When passive investment income exceeds $50,000, your small business deduction begins to "grind down." Only 50% of capital gains count toward this threshold, making capital gains strategies even more valuable. Learn more about the [SBD grind](/learn/sbd-grind/).
Consider Tax-Sheltered Alternatives
For long-term wealth transfer, consider corporate-owned life insurance, which provides tax-deferred growth and tax-free distribution through the CDA. This can be especially valuable for estate strategy. See our [case studies](/case-studies/) for examples.
Coordinate with Personal Accounts
Your corporate account is one piece of your total wealth picture. Keep interest-generating assets in personal TFSA or RRSP accounts when possible, and use your corporate account for capital gains strategies. Coordinate with RRSP, TFSA, and personal accounts to optimize your overall tax efficiency. Learn about [corporate vs personal investing](/learn/corporate-investing-vs-personal/).
Review Annually with Your CPA
Tax rules change, your situation evolves, and optimization opportunities shift. Review your tax strategy annually with your CPA to ensure you're maximizing tax efficiency while maintaining compliance. See our [tax optimization strategies](/services/tax-optimization/).
Portfolio Optimization Strategies
Structure by Time Horizon
Short-term needs (operating reserves) should be in low-risk, liquid investments. Long-term surplus can be structured for tax efficiency using capital gains strategies. See our [corporate investing guide](/learn/corporate-investing-in-canada/) for a complete framework.
Think Long-Term and Multi-Generation
Corporate investing is about building long-term wealth. Consider how your portfolio structure supports not just your immediate needs, but also estate strategy and wealth transfer to the next generation. See our [dynasty approach](/dynasty-builder/).
Work with Your Professional Team
Portfolio optimization requires coordination between your investment advisor, CPA, and lawyer. Ensure your team understands your goals and works together to implement strategies that align with your long-term vision.
Ready to optimize your corporate investment structure?
Why is my after-tax IRR lower than my account statement's reported return?
Account statements show the time-weighted return on the portfolio — what a dollar that stayed invested for the full period would have earned. They do not subtract taxes paid from the operating account on investment income, and they ignore irregular deposits and withdrawals. After-tax IRR (XIRR) uses the actual dollar-weighted cash flows and subtracts taxes paid, producing a lower but more accurate figure for what your corporation really earned.
Should I use gross tax paid or net-of-RDTOH?
Use gross tax paid. The cash that left the corporation stopped compounding; that is what the IRR calculation needs to reflect. RDTOH is refunded only when eligible taxable dividends are paid to the shareholder — a future cash flow that should be modelled separately if and when those dividends are actually paid.
What period length is most meaningful for IRR?
10 years or more. Shorter windows (2-5 years) can be distorted by recent market conditions — a strong year skews results high and a weak year skews them low. A 10-year period includes at least one correction and one recovery on average, so the IRR is more representative of what the structure will earn going forward.
How does IRR differ from the yield or interest rate on a fund?
Yield is the income a fund pays out (distributions) divided by price. IRR is the annualized compounding rate of the entire investor experience — price changes, distributions, reinvestments, and taxes paid. Two investors in the same fund can earn very different IRRs depending on when they deposited, withdrew, and how their corporation was taxed on the distributions.
Does this calculator account for the SBD grind-down?
Indirectly. The SBD grind increases the corporate tax on active business income once passive investment income crosses $50,000. That shows up as higher corporate tax paid, which is captured in the 'taxes paid on investment income' step. For a more explicit view of the grind itself, use the SBD Grind-Down Calculator.
Summary
Most corporate investors see their account grow but don't know their true after-tax internal rate of return (IRR). Taxes paid from the operating account reduce real returns but are invisible on the investment statement. This calculator computes after-tax IRR using XIRR methodology across a user-supplied date range, cash flows, and taxes paid on investment income.
The CDA lets a Canadian corporation pay tax-free dividends from capital gains and life insurance proceeds. How it works and how to use it....
Authoritative Canadian sources referenced on this page
Content on this page reflects, summarizes, or relies on the following public regulatory and taxation authorities. Consult the primary sources directly for definitive rules.
Financial Security Advisor · Mutual Fund Dealing Representative · Group Insurance & Annuity Plans Advisor
Independent advisor since 2008, focused on corporate investing, tax-efficient wealth strategies, and dynasty planning for incorporated business owners in Québec and Ontario. Mutual funds distributed through WhiteHaven Securities Inc.; insurance through iAssure Inc.
This content is for information and education only. It explains general concepts that may apply to incorporated business owners, but it is not personalized tax, legal, or investment advice.
Tax Considerations:
Tax rules are complex and subject to change
Strategies and benefits depend on your specific circumstances, province, and business structure
Always consult with a qualified CPA before implementing any tax strategy
Provincial variations in rates and rules may apply (Québec vs. Ontario differences exist)
Past tax treatment does not guarantee future treatment
Investment Risk Disclosure:
Investing involves risk, including the possible loss of principal
There is no guarantee that any investment strategy will achieve its objectives
Investment values fluctuate with market conditions, and you may receive less than you originally invested
Tax efficiency is one factor; risk, fees, and total returns all matter
Past performance does not guarantee future results
Insurance Illustrations:
Insurance illustrations show projected values based on assumptions that may not be guaranteed
Actual results will vary based on factors including interest rates, mortality experience, and expenses
Non-guaranteed elements (such as dividends or credited interest rates) are not promises of future performance
Review both guaranteed and non-guaranteed projections with your advisor before making decisions
Content Accuracy:
We strive to ensure information is accurate and current, but laws and regulations change frequently
Information reflects our understanding at the time of publication and may not reflect subsequent changes
If you believe any content contains an error, please contact us
Regulatory:
Mutual funds are offered through WhiteHaven Securities Inc.
Insurance products and certain other services are provided through iAssure Inc., an independent firm in the insurance of persons and in the group insurance of persons
These activities are neither the business nor the responsibility of WhiteHaven Securities Inc.
Professional Advice:
This article is not a substitute for professional advice from your CPA, lawyer, or financial advisor
Work with your professional team to understand how these concepts apply to your specific situation
For personalized advice, a formal engagement and suitability review are required
