Canadian Business Tax Calculator (Estimate)
Use this quick tool to estimate corporate income tax and GST/HST for a Canadian business.
How this business tax calculator Canada tool works
This page gives you a practical estimate of how much corporate income tax your business may owe in Canada. It combines a simplified federal + provincial corporate tax model with an optional GST/HST estimate. You can use it for quick planning, monthly cash flow projections, and quarterly tax installment prep.
The calculator is designed mainly for incorporated businesses. If you run a sole proprietorship, your business income is typically taxed on your personal return, which uses a different method.
What gets calculated
- Net business income (taxable income estimate) = Revenue - Expenses - Salary/Bonuses - Other Deductions
- Small business rate portion on eligible income (up to CAD 500,000 by default)
- General corporate rate portion for income above that amount
- Total estimated corporate income tax
- After-tax business profit
- Estimated monthly tax set-aside to help with budgeting
- Optional net GST/HST payable based on taxable sales and ITCs entered
Canadian corporate tax basics in plain language
1) Federal + provincial tax layers
Corporate tax in Canada is a combined system. You pay a federal portion and a provincial or territorial portion. Each province/territory has its own rates, which is why your tax estimate changes when you select a different location.
2) Small business deduction (SBD)
Many Canadian-controlled private corporations can access lower tax rates on active business income up to a limit. In this calculator, the lower rate is applied to up to CAD 500,000 by default unless you enter a custom eligible amount.
3) General corporate tax rate
Income above the small-business-eligible portion is taxed at the general combined corporate rate for your selected province/territory. This can significantly increase the overall effective tax rate as profits grow.
Combined tax rates used in this calculator
The calculator uses simplified combined (federal + provincial/territorial) rates for estimation:
- Alberta: 11% small business / 23% general
- British Columbia: 11% small business / 27% general
- Manitoba: 9% small business / 27% general
- New Brunswick: 11.5% small business / 29% general
- Newfoundland and Labrador: 12% small business / 30% general
- Nova Scotia: 11.5% small business / 29% general
- Northwest Territories: 11% small business / 26.5% general
- Nunavut: 12% small business / 27% general
- Ontario: 12.2% small business / 26.5% general
- Prince Edward Island: 10% small business / 31% general
- Quebec: 12.2% small business / 26.5% general (simplified)
- Saskatchewan: 10% small business / 27% general
- Yukon: 9% small business / 27% general
These are planning rates for quick estimates, not official filing calculations.
Example: quick planning scenario
Suppose an Ontario corporation has CAD 250,000 in revenue, CAD 80,000 in operating expenses, CAD 50,000 in salary, and CAD 5,000 in other deductions. Estimated taxable income is:
250,000 - 80,000 - 50,000 - 5,000 = 115,000
Since this is below the CAD 500,000 small-business threshold, the lower Ontario combined rate applies to all of it in this simplified model. The result is an easy estimate of corporate tax, after-tax profit, and a monthly tax reserve target.
GST/HST section: what it does and does not do
If you enter taxable sales and ITCs, the tool estimates your net GST/HST. This is not your corporate income tax, but a separate remittance obligation.
- Collected tax: Taxable sales × province GST/HST rate
- Net remittance: Collected tax - ITCs
- If ITCs exceed collected tax, the tool shows a potential refund position
Note: For GST-only provinces and territories this works as expected. Quebec QST and provincial retail sales taxes (where applicable) are not fully modeled.
Tax planning tips for Canadian business owners
- Track deductible expenses in real time, not just at year-end.
- Separate owner salary/dividend strategy with your accountant.
- Set aside cash monthly to avoid tax-time surprises.
- Review SBD eligibility annually, especially if your structure changes.
- Keep GST/HST filings current to avoid penalties and interest.
- Use quarterly estimate reviews if your revenue is seasonal.
Important limitations
This business tax calculator Canada page is educational and for rough planning only. It does not include every variable used in real corporate tax returns. For example, it does not fully model loss carryforwards, passive income rules, detailed credits, capital gains treatment, provincial surcharges, or complex intercompany structures.
Always confirm final tax with a qualified CPA or tax professional before filing or making major financial decisions.
FAQ
Can I use this calculator if I am self-employed but not incorporated?
You can use it for rough profit planning, but personal tax calculations for sole proprietors are different. Use a personal income tax model for filing accuracy.
Does this replace professional tax advice?
No. It is a fast estimate tool, not legal, accounting, or tax advice.
Why does my effective tax rate look low?
If your taxable income stays within the small-business-eligible portion, your blended corporate tax rate can be much lower than the general corporate rate.