This page describes the sourcing, accuracy, and update rules that apply to every calculator on this site.
Source authority
Every calculator cites a primary source from one of the following categories:
- Canada Revenue Agency (CRA) for federal tax, RRSP, TFSA, FHSA, RESP, HBP, CCB, GST/HST credit, Canada Workers Benefit, Canada Carbon Rebate, and GST/HST registration rules.
- Service Canada + Employment and Social Development Canada (ESDC) for CPP, OAS, GIS, EI, and federal disability programs.
- Retraite Québec + Revenu Québec for QPP, Quebec tax, Quebec welcome tax, Quebec Solidarity Tax Credit, and Quebec-specific programs.
- Provincial finance ministries and land titles offices for provincial income tax brackets, sales tax, land transfer tax, and foreign buyer additional taxes.
- Canada Mortgage and Housing Corporation (CMHC) and OSFI for mortgage insurance premiums, the B-20 stress test, and qualifying rate rules.
- Statistics Canada for inflation, indexation, and benchmark economic figures where applicable.
When a source is used, the calculator page displays the source name, a direct link, and a last-verified date.
How numbers are kept current
Every calculator is manually verified against its official source at least once per year. This happens in January after the federal government’s annual indexation announcement. Pages updated outside that cycle (e.g., mid-year bracket changes, new programs, rate resets) display a newer “last verified” date.
The “last verified” date on any page is a commitment. If you see a date older than 12 months on a calculator that should have changed (tax brackets, contribution limits, insurance premiums), use the contact form and I will update it that day.
Calculation methodology
Calculators implement the rules as published by the relevant authority. Where the underlying math involves compounding, the following Canadian conventions apply:
- Mortgage payments use semi-annual compounding with monthly payment frequency, consistent with Canadian mortgage law (Interest Act).
- Investment growth calculations offer user-selectable compounding frequency (annual, semi-annual, monthly, daily).
- Tax calculations use marginal bracket math with basic personal amount credits applied at the lowest-bracket rate.
- Benefit calculations use the phase-in and phase-out formulas published by the administering agency, not simplified approximations.
What calculators do not do
- Calculators do not recommend specific financial products, tax software, lenders, or service providers. Where a type of professional is needed (e.g., “consult a family lawyer before signing a separation agreement”), the calculator says so but does not refer to a specific firm.
- Calculators assume standard cases. Edge cases involving non-resident filers, trusts, estates in dispute, bankruptcy, or other complex situations require professional review. Calculators flag known edge cases in the result interpretation.
- Calculators are updated for the tax year or benefit year they claim to cover. Year-specific calculators (e.g., “2025 tax brackets”) will not be silently updated to other years without a new URL or a visible title change.
Accuracy commitment
If you believe a number on this site is wrong, send the page URL and the correct figure with its official source link via the corrections contact. Corrections are prioritized over all other work. Published corrections include a dated changelog note on the affected page.
Content independence
No third party pays to influence what this site publishes or how calculators are framed. Where affiliate links appear (in designated resources blocks, never in calculator output), the placement is disclosed and the recommendation is not contingent on the affiliate relationship.
If you’re a government agency or publisher who needs a figure updated on this site, use the corrections contact. I don’t charge for corrections and I don’t require approval from anyone before publishing them.